{"title":"Field Flatteners \u0026 Reducers","description":"\u003cdiv\u003e\n  \u003cp\u003eMost refractors and Schmidt-Cassegrains focus light onto a slightly curved surface, while camera sensors are flat. The centre stays sharp, but toward the corners stars stretch into lines. A field flattener corrects the curvature so stars stay round across the sensor. A reducer-flattener does the same and also shortens the focal length, for a wider field and faster exposures.\u003c\/p\u003e\n  \u003cp\u003eEach corrector is designed for specific telescopes and a specific back-focus. We carry flatteners and reducers from Askar, William Optics, Sky-Watcher, Celestron, SharpStar, Baader, ZWO, Starizona, Tele Vue, SVBONY and Explore Scientific, and we will tell you which one belongs on your tube.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c!-- more --\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eFlattener or Reducer?\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003e\n\u003cstrong\u003e1.0x flattener:\u003c\/strong\u003e Keeps native focal length. Best for small targets and when your camera's pixel scale already suits the telescope.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003e0.7x to 0.85x reducer-flattener:\u003c\/strong\u003e Wider field and faster focal ratio. A 0.8x reducer cuts exposure time by about a third.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSCT reducers:\u003c\/strong\u003e f\/6.3 reducer-corrector for standard SCTs, 0.7x reducer for EdgeHD.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eDedicated or universal:\u003c\/strong\u003e A corrector designed for your exact telescope almost always beats a universal one, especially with larger sensors.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eGetting the Back-Focus Right\u003c\/h2\u003e\n  \u003cp\u003eEach corrector has a required distance to the sensor, often 55 mm but not always. Too short or too long and corner stars stretch. Plan the \u003ca href=\"\/en-int\/collections\/imaging-train\"\u003eimaging train\u003c\/a\u003e before ordering.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eWhat We Confirm\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003e\n\u003cstrong\u003eModel match:\u003c\/strong\u003e We confirm which corrector the manufacturer designed for your telescope and its focuser thread.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eImage circle:\u003c\/strong\u003e We check that the corrected field covers your sensor.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSpacing:\u003c\/strong\u003e We give you the full list of spacers to reach the exact distance.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eFlatteners and Reducers: Frequently Asked Questions\u003c\/h2\u003e\n  \u003ch3\u003eDoes my telescope need a flattener?\u003c\/h3\u003e\n  \u003cp\u003eDoublets and triplets used with anything larger than a small sensor almost always do. Petzval and quintuplet designs have one built in.\u003c\/p\u003e\n  \u003ch3\u003eCan I use a flattener for visual observing?\u003c\/h3\u003e\n  \u003cp\u003eIt works but adds glass and back-focus. Most observers remove it for visual use.\u003c\/p\u003e\n  \u003ch3\u003eMy corner stars are still elongated. What now?\u003c\/h3\u003e\n  \u003cp\u003eSend us a raw image. Stars pointing toward the centre mean spacing is too short; pointing away means too long.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eWhich corrector fits your telescope?\u003c\/h2\u003e\n  \u003cp\u003eSend us your telescope model and camera. We will name the corrector and the spacing.\u003c\/p\u003e\n\u003c\/div\u003e\n","products":[{"product_id":"celestron-reducer-corrector","title":"Celestron Reducer - Corrector","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces telescope focal length by 37%\u003c\/li\u003e\n\u003cli\u003eConverts f\/10 SCTs to f\/6.3 and f\/11 systems to f\/7\u003c\/li\u003e\n\u003cli\u003eCompatible with Celestron C5, C6, C8, C9.25, C11, and C14 SCTs\u003c\/li\u003e\n\u003cli\u003eFully multi-coated optics for maximum light transmission\u003c\/li\u003e\n\u003cli\u003eWeighs just 4.3 oz (121.90 g)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eCelestron f\/6.3 Reducer - Corrector\u003c\/h2\u003e\n\u003cp\u003eThe Celestron Reducer - Corrector transforms your \u003ca href=\"\/en-int\/collections\/schmidt-cassegrain-telescopes\"\u003eSchmidt-Cassegrain telescope\u003c\/a\u003e, effectively giving you two instruments in one by reducing the focal length by 37% to convert a native f\/10 system into a faster f\/6.3 optical train. This fully multi-coated lens threads directly onto the rear cell of C5 to C14 SCTs, weighs only 4.3 oz (121.90 g), and measures 56mm in diameter. For astrophotographers, this focal reduction shortens exposure times by more than half, allowing you to capture faint deep-sky objects with greater efficiency.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eConvert f\/10 to f\/6.3: A 37% Focal Length Reduction\u003c\/h3\u003e\n\u003cp\u003eThis corrector-reducer lens alters the primary optical characteristics of your standard SCT. By reducing the focal length by 37%, it changes an f\/10 telescope to a much faster f\/6.3 system, and an f\/11 telescope to f\/7. This has profound benefits for both visual observation and imaging.\u003c\/p\u003e\n\u003cp\u003eVisually, you achieve a wider true field of view with any given \u003ca href=\"\/en-int\/collections\/eyepieces\"\u003eeyepiece\u003c\/a\u003e, making it easier to locate objects and frame large targets like the Andromeda Galaxy (M31) or the Pleiades (M45). For imaging, the faster focal ratio dramatically cuts down on necessary exposure time, allowing you to gather the same amount of signal in about 40% of the time required at f\/10.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFor C5 to C14 Standard SCTs: Visual and Photographic Use\u003c\/h3\u003e\n\u003cp\u003eThis reducer is designed specifically for Celestron's standard line of Schmidt-Cassegrain telescopes, offering broad compatibility from the portable C5 up to the observatory-class C14. It threads directly onto the rear cell, creating a secure connection for your imaging train or \u003ca href=\"\/en-int\/collections\/visual-adapters\"\u003evisual back\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003eOnce installed, you can attach standard accessories like a \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-Adapter\u003c\/a\u003e for your DSLR or a 1.25\" visual back for \u003ca href=\"\/en-int\/collections\/diagonals\"\u003ediagonals\u003c\/a\u003e and eyepieces. While it does provide some field-flattening for improved edge-of-field sharpness, its primary function is focal reduction, making it an essential tool for deep-sky astrophotography with non-EdgeHD optical tubes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e4.3 oz Machined Aluminum Body with Fully Multi-Coated Optics\u003c\/h3\u003e\n\u003cp\u003eEngineered for durability and optical clarity, the reducer is housed in a precisely machined aluminum body with a black anodized finish, weighing a mere 4.3 oz. The internal surfaces are blackened and glare-threaded to suppress internal reflections and maximize image contrast, ensuring a dark sky background.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFully Multi-coated Lenses:\u003c\/strong\u003e Every air-to-glass surface features high-transmission coatings to ensure maximum light throughput and minimal reflection, preserving the brightness and fidelity of the image.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eKnurled Grip:\u003c\/strong\u003e A textured, knurled surface provides a secure grip for easy threading and unthreading, even when wearing gloves in cold conditions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompact Design:\u003c\/strong\u003e At only 34mm (1.34\") in length, it adds minimal backfocus to your optical train, preserving compatibility with most existing accessories.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eStandard SCT vs. EdgeHD: Why This Reducer is Not for EdgeHD Optics\u003c\/h3\u003e\n\u003cp\u003eIt is critical to note that this f\/6.3 reducer is engineered for standard Schmidt-Cassegrain telescopes only and is not compatible with Celestron's EdgeHD optical tubes. EdgeHD telescopes have a built-in flattener and require a dedicated, optically matched reducer (like the Celestron .7x Reducer) to maintain their flat-field, coma-free imaging circle.\u003c\/p\u003e\n\u003cp\u003eUsing this standard reducer on an EdgeHD telescope will result in degraded optical performance and will not achieve the designed image quality of the EdgeHD system. If you own an EdgeHD scope, you must use the reducer specifically designed for that optical system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Celestron f\/6.3 Reducer change the view in my 8\" f\/10 SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn a Celestron 8\" SCT with a native 2032mm focal length, this reducer converts it to approximately 1280mm at f\/6.3. With a 25mm eyepiece, your magnification would drop from 81x to 51x, and your field of view would become significantly wider, making it easier to fit large deep-sky objects like the Orion Nebula (M42) into a single frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use this Reducer - Corrector with an Off-Axis Guider (OAG)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, you can use an \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eOAG\u003c\/a\u003e with this reducer. The Off-Axis Guider is among the accessories you can add after the reducer.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy can't I use this reducer on my Celestron EdgeHD 9.25\" telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eEdgeHD optical systems are designed with an integrated field flattener to provide a perfectly flat field for imaging. They require a specific, matched 0.7x reducer lens that is designed to work with that flattened field. Using this standard f\/6.3 reducer on an EdgeHD will introduce optical aberrations and will not maintain the edge-to-edge sharpness that is the primary feature of the EdgeHD design.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes this reducer completely eliminate field curvature in my standard SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, it does not completely eliminate it. While the Celestron Reducer - Corrector does diminish some of the inherent field curvature of a standard SCT, its primary purpose is focal length reduction. You will notice flatter fields and sharper stars at the edge compared to using the telescope at its native focal length, but it does not produce a perfectly flat field like an EdgeHD system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs this Celestron Reducer - Corrector compatible with non-Celestron SCTs?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis reducer is optically designed and optimized for Celestron Schmidt-Cassegrain telescopes. While it may physically thread onto other brands of SCTs that use the standard 2\" rear cell thread, optical performance is not guaranteed and may vary.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eReducer - Corrector\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLens Coatings\u003c\/td\u003e\n\u003ctd\u003eFully Multi-coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Reduction\u003c\/td\u003e\n\u003ctd\u003e0.63x (37% reduction)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBody Material\u003c\/td\u003e\n\u003ctd\u003eMachined aluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatibility\u003c\/td\u003e\n\u003ctd\u003eCelestron C5, C6, C8, C9.25, C11, C14 (Standard SCTs only)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIncompatible With\u003c\/td\u003e\n\u003ctd\u003eEdgeHD, Maksutov-Cassegrain, Refractor, Newtonian Telescopes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDiameter\u003c\/td\u003e\n\u003ctd\u003e56mm (2.2\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLength\u003c\/td\u003e\n\u003ctd\u003e34mm (1.34\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e4.3 oz (121.90 g)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003eSCT 2\"-24tpi female\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eSCT 2\"-24tpi male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cimg class=\"DAV-img-box\" alt=\"Celestron Reducer - Corrector\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/celestron-reducer-corrector-1.jpg?v=1638308400\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eCelestron f\/6.3 Reducer - Corrector\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cimg class=\"DAV-img-box\" alt=\"Front Dust Cap\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/celestron-reducer-corrector-cap-1.jpg?v=1638308401\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eFront Dust Cap\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cimg class=\"DAV-img-box\" alt=\"Rear Dust Cap\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/celestron-reducer-corrector-cap-2.jpg?v=1638308402\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eRear Dust Cap\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967145832733,"sku":"CEL-94175","price":278.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-Reducer-Corrector-94175-1__19018.1594230247.1280.1280.jpg?v=1684337165"},{"product_id":"celestron-reducer-lens-7x-edgehd-1100","title":"Celestron Reducer Lens .7x - EdgeHD 1100","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces EdgeHD 1100 focal ratio to f\/7\u003c\/li\u003e\n\u003cli\u003e5-element optical design with Lanthanum glass\u003c\/li\u003e\n\u003cli\u003eIncreases field of view by 43%\u003c\/li\u003e\n\u003cli\u003eMaintains EdgeHD flat-field imaging performance\u003c\/li\u003e\n\u003cli\u003eProvides a generous 146mm of back focus\u003c\/li\u003e\n\u003cli\u003eOptimized for a 42mm full-frame image circle\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eCelestron Reducer Lens .7x - EdgeHD 1100\u003c\/h2\u003e\n\u003cp\u003eThe Celestron Reducer Lens .7x for the EdgeHD 1100 is a purpose-built, 5-element optical corrector that transforms your telescope into a faster, wider imaging system without compromising its acclaimed flat-field correction. This reducer provides a generous 146mm of back focus for complex imaging trains and increases your field of view by 43%, allowing you to capture expansive nebulae and galaxies within a 42mm full-frame image circle.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 5-Element System to Maintain Flat-Field Correction\u003c\/h3\u003e\n\u003cp\u003eUnlike generic reducers that can introduce field curvature, this .7x reducer features a custom 5-element optical design engineered specifically to work with the EdgeHD 1100 system. It uses high-index Lanthanum glass elements to minimize chromatic aberration and preserve the pinpoint stars from the center to the edge of the field. All air-to-glass surfaces are fully multi-coated, and lens edges are blackened to ensure maximum light transmission and image contrast.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e.7x Reduction for f\/7.7 Speed and a 43% Wider View\u003c\/h3\u003e\n\u003cp\u003eBy applying a .7x compression factor, this reducer lens effectively shortens your telescope's focal length, making it one full f-stop faster. This converts the EdgeHD 1100 from f\/10 to a speedier f\/7, cutting your required exposure time in half. This speed advantage is paired with a 43% increase in the field of view, enabling you to frame large deep-sky objects like the Andromeda Galaxy (M31) or the Orion Nebula (M42) in their entirety.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e146mm Back Focus for Full-Frame Sensors and Accessories\u003c\/h3\u003e\n\u003cp\u003eDesigned for modern astrophotography, the reducer provides 146mm (5.75\") of optimal back focus, accommodating a wide range of cameras, \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e, and \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e. It threads directly onto the EdgeHD 1100's 3.25\" rear cell, and its 60mm clear aperture is optimized for a 42mm image circle and reduces mechanical vignetting. This robust connection and generous spacing make it the ideal solution for imagers using full-frame DSLR, mirrorless, or dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the .7x reducer change the EdgeHD 1100's focal length and f-ratio?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Celestron .7x Reducer converts the EdgeHD 1100's native 2800mm focal length at f\/10 to approximately 1960mm at f\/7. This makes the system significantly faster, reducing exposure times by 50% for the same image brightness.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the benefit of the 146mm back focus on the EdgeHD 1100 reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003e146mm back focus\u003c\/strong\u003e provides ample space to install a full imaging train behind the reducer. This allows you to comfortably fit accessories like an off-axis guider (OAG), a filter wheel, and your camera without running out of spacing, a common issue with generic reducers.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this reducer work with my full-frame camera on the EdgeHD 1100?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer is designed with a large 60mm clear aperture optimized for a 42mm image circle, and Celestron designed it for use with larger (full frame) sensors. A full-frame diagonal (about 43mm) is slightly larger than the 42mm circle, so expect some light falloff in the extreme corners.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is this dedicated reducer better than a generic SCT reducer for my EdgeHD 1100?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA generic \u003ca href=\"\/en-int\/collections\/schmidt-cassegrain-telescopes\"\u003eSchmidt-Cassegrain\u003c\/a\u003e reducer is not designed to preserve the advanced, flat-field optical correction of the EdgeHD system. This dedicated \u003cstrong\u003e5-element reducer\u003c\/strong\u003e is optically matched to the EdgeHD 1100, ensuring it maintains the flat field and pinpoint stars while a generic reducer would likely reintroduce field curvature and other aberrations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does this reducer help when imaging large targets like the Andromeda Galaxy (M31) with an EdgeHD 1100?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAt its native focal length, an EdgeHD 1100 is too magnified to fit the entire Andromeda Galaxy (M31) in a single frame with most sensors. The reducer's \u003cstrong\u003e43% wider field of view\u003c\/strong\u003e makes it possible to capture the galaxy from core to outer arms, making it an essential accessory for wide-field deep-sky imaging.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes this reducer affect the flat-field correction of the EdgeHD 1100 optics?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, it is designed to maintain it. The primary purpose of this reducer's custom 5-element design is to reduce the focal length while preserving the coma-free, flat-field performance that is the hallmark of the EdgeHD optical system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e5-Element\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompression Factor\u003c\/td\u003e\n\u003ctd\u003e.7x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptimal Back Focus\u003c\/td\u003e\n\u003ctd\u003e146mm (5.75\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e42mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e60mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Coatings\u003c\/td\u003e\n\u003ctd\u003eFully Multi-Coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGlass Type\u003c\/td\u003e\n\u003ctd\u003eLanthanum Elements\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e3.25 lbs (1.47 kg)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eEdgeHD 3.25\" thread Female\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for (scopes \/ focal range)\u003c\/td\u003e\n\u003ctd\u003eEdgeHD 1100\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e0.7x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned For\u003c\/td\u003e\n\u003ctd\u003eEdgeHD 1100 (EdgeHD 11\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e.7x Reducer Lens for EdgeHD 1100\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eThreaded Metal Dust Covers\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 2\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.celestron.com\/pages\/drivers-and-software\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Limited Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967145865501,"sku":"CEL-94241","price":1180.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-Reducer-Lens-7x-EdgeHD-1100-94241-1__77053.1594230247.1280.1280.jpg?v=1684337161"},{"product_id":"celestron-reducer-lens-7x-edgehd-1400","title":"Celestron Reducer Lens .7x - EdgeHD 1400","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces EdgeHD 1400 focal ratio by a factor of 0.7x\u003c\/li\u003e\n\u003cli\u003eCustom 5-element optical design preserves flat-field imaging\u003c\/li\u003e\n\u003cli\u003eProvides a generous 146mm of back focus for imaging equipment\u003c\/li\u003e\n\u003cli\u003eDelivers a 42mm image circle for use with large (full frame) sensors\u003c\/li\u003e\n\u003cli\u003eFeatures exotic Lanthanum glass elements to minimize chromatic aberration\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eCelestron Reducer Lens .7x - EdgeHD 1400\u003c\/h2\u003e\n\u003cp\u003eThe Celestron Reducer Lens .7x for the EdgeHD 1400 is an optically-matched corrector that transforms the telescope into a faster, wider imaging system without compromising its flat-field correction. Its 5-element design reduces the focal ratio from f\/11 to f\/7.7, increasing the field of view by 43% while cutting required exposure times in half. Engineered with 146mm of back focus and a 42mm image circle, this 3.25 lb reducer accommodates large-sensor CCD and DSLR cameras with accessories like \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e and \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e5-Element Optics: Maintaining Flat-Field EdgeHD Correction\u003c\/h3\u003e\n\u003cp\u003eUnlike a generic reducer, this 5-element lens is designed specifically to work with the EdgeHD 1400's optical system, ensuring the field remains perfectly flat from corner to corner on the sensor. Celestron uses high-index, \"rare earth\" Lanthanum glass elements to provide high-contrast views and minimize chromatic aberration, delivering sharp stars with no color fringing. All air-to-glass surfaces are fully multi-coated for maximum light transmission, while blackened lens edges prevent internal reflections from reducing image contrast.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eImaging at f\/7.7: A 43% Wider Field and Halved Exposure Times\u003c\/h3\u003e\n\u003cp\u003eThe primary purpose of the 0.7x reducer is to make the EdgeHD 1400 a more capable deep-sky imaging instrument. By reducing the focal length, it increases the true field of view by 43%, allowing you to frame large targets like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000) in their entirety. This reduction also makes the telescope one full f-stop faster, reducing the required imaging exposure time by half to achieve the same signal-to-noise ratio.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e146mm Back Focus: Integrating Full-Frame Cameras and Accessories\u003c\/h3\u003e\n\u003cp\u003eA critical advantage of this reducer is its substantial 146mm (5.75\") of optimal back focus, providing ample space for complex imaging trains. This allows you to easily incorporate accessories like an off-axis guider, filter wheel, or adaptive optics system without struggling to reach focus. The optical design delivers a corrected 42mm image circle, which allows use with larger (full frame) sensors, making it a professional-grade solution for serious astrophotography.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eMechanical Design: A 60mm Aperture with a 3.29\" Thread-On Interface\u003c\/h3\u003e\n\u003cp\u003eThe reducer's housing is CNC machined from aluminum for precise optical alignment and thermal stability. It threads directly onto the 3.29\"-16 tpi threaded baffle tube lock nut on the back of the EdgeHD 1400, a large connection that reduces mechanical vignetting. With a clear aperture of 60mm, the reducer ensures that the full 42mm corrected image circle reaches the sensor, maximizing the performance of your telescope and camera system. Threaded metal covers are included to protect the optics from dust and scratches when not in use.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main benefit of the EdgeHD 1400 .7x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer makes the telescope \"faster\" and \"wider.\" It reduces the focal ratio from f\/11 to a faster f\/7.7, which cuts your exposure times in half. It also increases the field of view by 43%, allowing you to capture larger deep-sky objects that would not fit in the frame at the native focal length.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I set the correct 146mm back focus for my camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 146mm distance is measured from the rear flange of the reducer to your camera's sensor. You will need to use a combination of \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-adapters\u003c\/a\u003e and extension tubes to achieve this precise spacing. You must account for the optical path length of any accessories, such as an off-axis guider or filter wheel, when calculating the required extensions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use this reducer with a full-frame camera on my EdgeHD 1400?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. This reducer is designed to produce a \u003cstrong\u003e42mm corrected image circle\u003c\/strong\u003e, which Celestron designed for use with larger (full frame) sensors; a full-frame sensor's ~43mm diagonal is slightly larger than that circle, so expect some light falloff in the extreme corners, which flat frames correct.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this reducer work on an 11\" or 9.25\" EdgeHD telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. Each EdgeHD reducer is optically matched to a specific telescope aperture to maintain the system's flat-field correction. Using the 14\" reducer on a smaller EdgeHD telescope will result in poor image quality. You must use the reducer designed for your specific model.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the .7x Reducer affect imaging the Orion Nebula (M42) with an EdgeHD 1400?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWith the reducer, you can capture the full expanse of the Orion Nebula, including its faint outer wings and the nearby Running Man Nebula (NGC 1977), in a single frame. At the native f\/11, you would only be able to frame the core Trapezium region, requiring a multi-panel mosaic to capture the entire complex.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the EdgeHD 1400 Reducer compatible with the Fastar system?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer is used on the rear cell of the telescope for f\/7.7 imaging. The Fastar system operates independently by replacing the secondary mirror for ultra-fast f\/2 imaging. Together, they make the EdgeHD 1400 an incredibly versatile imaging platform, offering three distinct focal ratios in one telescope.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Coatings\u003c\/td\u003e\n\u003ctd\u003eFully Multi-Coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLens Elements\u003c\/td\u003e\n\u003ctd\u003e5-Element\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompression Factor\u003c\/td\u003e\n\u003ctd\u003e0.7x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e42mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptimal Back Focus\u003c\/td\u003e\n\u003ctd\u003e146mm (5.75\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e60mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConnection to Telescope\u003c\/td\u003e\n\u003ctd\u003e3.29\"-16 tpi Threads (EdgeHD rear thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e3.25 lbs (1.47 kg)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eCelestron EdgeHD 14\" (1400)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-side connection\u003c\/td\u003e\n\u003ctd\u003eEdgeHD 3.29\"-16tpi Male (fits Large T-Adapter #93646)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003eCelestron EdgeHD female\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eReducer Lens .7x for EdgeHD 1400\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eThreaded Metal Dust Cap (Front)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eThreaded Metal Dust Cap (Rear)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Celestron_EdgeHD_Optics_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload EdgeHD Reducer Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Celestron-EdgeHD-Optics-Whitepaper.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload EdgeHD Whitepaper\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.celestron.com\/pages\/drivers-and-software\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Celestron Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Limited Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967145931037,"sku":"CEL-94240","price":1180.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-Reducer-Lens-7x-EdgeHD-1400-94240-1__12070.1594230248.1280.1280.jpg?v=1684337166"},{"product_id":"celestron-reducer-lens-7x-edgehd-800","title":"Celestron Reducer Lens .7x - EdgeHD 800","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal length by a factor of 0.7x, changing the EdgeHD 800 from f\/10 to f\/7\u003c\/li\u003e\n\u003cli\u003e4-element optical design maintains the native flat-field performance of the EdgeHD system\u003c\/li\u003e\n\u003cli\u003eIncreases the field of view by 43%, ideal for capturing large celestial objects\u003c\/li\u003e\n\u003cli\u003eProvides a generous 105mm of back focus for compatibility with a wide range of cameras and accessories\u003c\/li\u003e\n\u003cli\u003eFully multi-coated optics with Lanthanum glass elements maximize light transmission and minimize chromatic aberration\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eCelestron Reducer Lens .7x - EdgeHD 800\u003c\/h2\u003e\n\u003cp\u003eThe Celestron Reducer Lens .7x for the EdgeHD 800 is a custom-engineered 4-element optical accessory that transforms the telescope's native f\/10 system into a faster f\/7 instrument. This 0.7x compression factor increases the field of view by 43%, allowing you to capture expansive nebulae and galaxies within a single frame. The design provides a substantial 105mm of back focus, accommodating complex imaging trains with \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e, \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e, and a wide variety of dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 4-Element Design for Flat-Field Imaging\u003c\/h3\u003e\n\u003cp\u003eUnlike a generic reducer, the Celestron .7x Reducer is engineered specifically to work with the EdgeHD 800's optical system. Its 4-element design, which incorporates high-index Lanthanum glass, maintains the flat-field, coma-free performance the EdgeHD is known for, ensuring sharp stars from the center to the edge of the frame. All air-to-glass surfaces are fully multi-coated to maximize light transmission and eliminate chromatic aberration, preserving the high-contrast views of the original optical design.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 43% Wider Field and 0.7x Faster Exposures\u003c\/h3\u003e\n\u003cp\u003eBy reducing the focal length, this accessory widens your field of view by 43%, making it possible to frame large targets like the Andromeda Galaxy (M31) or the Orion Nebula (M42) in their entirety. This focal reduction also makes the optical system one full f-stop faster, cutting required exposure times in half. You can gather the same amount of signal in a 5-minute sub-exposure as you would in a 10-minute exposure at f\/10, reducing demands on your mount's tracking and minimizing noise.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eCNC Machined Housing and 105mm Back Focus\u003c\/h3\u003e\n\u003cp\u003eThe reducer's housing is CNC machined from aluminum for precise optical alignment and spacing, critical for maintaining image quality. A key feature is the generous 105mm of optimal back focus, measured from the reducer's rear flange. This provides ample room for accessories like off-axis guiders, filter wheels, and adaptive optics systems without compromising the flat-field correction, a significant advantage over reducers with shorter back focus requirements.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eThe f\/7 Midpoint for the EdgeHD 800\u003c\/h3\u003e\n\u003cp\u003eThe .7x Reducer gives your EdgeHD 800 a versatile f\/7 focal ratio, creating a three-in-one imaging platform. This provides a crucial intermediate step between the telescope's native f\/10 for high-resolution planetary and small galaxy imaging, and the ultra-fast f\/2 ratio available with the optional HyperStar accessory for wide-field surveys. This flexibility makes the EdgeHD 800, equipped with the .7x reducer, one of the most complete imaging systems available.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the 105mm back focus on the EdgeHD 800 Reducer mean for my imaging setup?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 105mm back focus is the required distance from the reducer's rear mounting flange to your camera's sensor for optimal flat-field performance. This generous distance allows you to easily install accessories like an off-axis guider (OAG), filter wheel, and various adapters in your imaging train while still hitting the correct spacing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the .7x Reducer help when imaging the Andromeda Galaxy (M31) with an EdgeHD 800?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAt its native f\/10 focal length, an EdgeHD 800 is too magnified to capture the full Andromeda Galaxy. The .7x Reducer increases the field of view by 43%, allowing you to frame the entire galaxy and its companions, M32 and M110, in a single shot with an APS-C or smaller sensor. It also reduces exposure time, making it easier to capture the faint outer dust lanes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this reducer work with a full-frame camera on my EdgeHD 800?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eCelestron optimizes this reducer for APS-C sized sensors, including most DSLR cameras, and smaller astronomy cameras. It is not rated for full-frame sensors, so expect vignetting and softer corners if you use one.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Celestron .7x Reducer better than a generic focal reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. Generic reducers are not designed to correct for the specific field curvature of the EdgeHD optical system. The Celestron .7x Reducer uses a custom 4-element design to maintain the flat, coma-free field across the entire image, ensuring sharp stars to the corners where a generic reducer would show distortion.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow much faster is imaging with the EdgeHD 800 Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer changes the telescope's focal ratio from f\/10 to f\/7. This is one full f-stop faster, which means it cuts the required exposure time in half. For example, a 10-minute exposure at f\/10 can be achieved in just 5 minutes at f\/7 with the same image brightness.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need any special adapters to connect my DSLR to the .7x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. You will need a \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e for your specific camera brand (e.g., Canon, Nikon) and a T-adapter that provides the correct spacing to achieve the 105mm back focus. Celestron offers T-adapters designed for the EdgeHD series that simplify this process.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e4-element\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompression Factor\u003c\/td\u003e\n\u003ctd\u003e0.7x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLens Elements\u003c\/td\u003e\n\u003ctd\u003e4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGlass Types\u003c\/td\u003e\n\u003ctd\u003eLanthanum Elements\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Coatings\u003c\/td\u003e\n\u003ctd\u003eFully Multi-Coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptimal Back Focus\u003c\/td\u003e\n\u003ctd\u003e105mm (4.13\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.8 lbs (0.36 kg)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003eSCT 2\"-24tpi female\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eSCT 2\"-24tpi male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned For\u003c\/td\u003e\n\u003ctd\u003eCelestron EdgeHD 800\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eReducer Lens .7x - EdgeHD 800\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eThreaded Metal Dust Cap (Front)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eThreaded Metal Dust Cap (Rear)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Celestron_.7x_Reducer_for_EdgeHD_800_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Reducer Lens .7x for EdgeHD 800 Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967145963805,"sku":"CEL-94242","price":582.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-Reducer-Lens-7x-EdgeHD-800-94242-1__43771.1594230248.1280.1280.jpg?v=1684337171"},{"product_id":"celestron-reducer-lens-7x-edgehd-925","title":"Celestron Reducer Lens .7x - EdgeHD 925","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal ratio by a factor of 0.7x for faster imaging\u003c\/li\u003e\n\u003cli\u003e4-element design maintains the native flat-field performance of the EdgeHD 9.25\"\u003c\/li\u003e\n\u003cli\u003eProvides an optimal back focus of 146mm for cameras and accessories\u003c\/li\u003e\n\u003cli\u003eOptimized for a 42mm image circle for use with full-frame sensors\u003c\/li\u003e\n\u003cli\u003eFeatures Lanthanum glass elements to minimize chromatic aberration\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eCelestron Reducer Lens .7x - EdgeHD 925\u003c\/h2\u003e\n\u003cp\u003eThe Celestron Reducer Lens .7x for the EdgeHD 9.25\" is a custom-engineered 4-element optic that transforms your telescope into a faster, wider imaging system. This reducer provides a generous 146mm of back focus, allowing complex imaging trains while maintaining the award-winning flat-field correction of the EdgeHD optical design from edge to edge.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 0.7x Reduction Factor with 4-Element Flat-Field Correction\u003c\/h3\u003e\n\u003cp\u003eThis dedicated reducer converts your f\/10 EdgeHD 9.25\" into an f\/7 system, effectively cutting your required exposure time in half to achieve the same image brightness. The 4-element optical layout is specifically designed to work with the EdgeHD optics, ensuring the pinpoint stars across a flat field are preserved. This means you can capture wide-field images of large galaxies and nebulae with a 43% wider field of view without sacrificing image quality at the edges.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eLanthanum Glass Elements for High-Contrast Imaging\u003c\/h3\u003e\n\u003cp\u003eUnlike generic reducers, the Celestron .7x Reducer uses high-index, exotic Lanthanum glass elements. This \"rare earth\" glass provides superior correction of chromatic aberration, resulting in images with higher contrast and neutral color balance. All air-to-glass surfaces are fully multi-coated for maximum light transmission, and the lens edges are blackened to eliminate internal reflections that can reduce image contrast.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFull-Frame Ready with 146mm of Optimal Back Focus\u003c\/h3\u003e\n\u003cp\u003eEngineered for modern astrophotography, this reducer features a 60mm clear aperture and produces an optimized 42mm image circle, for use with large CCD and CMOS sensors, including full frame. It threads directly onto the EdgeHD 9.25\" optical tube's 3.25\" port, creating a rigid connection. The design provides an optimal back focus distance of 146mm, accommodating accessories like \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e, \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e, and a wide range of cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main benefit of the Celestron .7x Reducer for my EdgeHD 9.25\"?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary benefit is speed. By converting your telescope from f\/10 to f\/7, it reduces your exposure time by 50%. It also widens your field of view by 43%, allowing you to fit larger celestial objects, like the Andromeda Galaxy (M31), into a single frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is a dedicated EdgeHD reducer better than a generic one?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe EdgeHD optical design produces a very flat, coma-free field. A generic reducer is not designed to preserve this correction and will introduce field curvature and other aberrations. The Celestron .7x Reducer is a \u003cstrong\u003e4-element\u003c\/strong\u003e system custom-designed to work with the EdgeHD 9.25\" optics to maintain its signature flat-field performance across the entire image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Celestron .7x Reducer help when imaging the Orion Nebula (M42) with an EdgeHD 925?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Orion Nebula (M42) is a large and bright target. The \u003cstrong\u003e0.7x\u003c\/strong\u003e reduction allows you to capture the full expanse of the nebula, including its fainter outer structures, in a single shot. The faster f\/7 focal ratio significantly shortens the sub-exposure times needed to capture the faint details without blowing out the bright core of the Trapezium cluster.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the 146mm back focus on the EdgeHD 925 reducer allow me to do?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 146mm back focus is measured from the telescope's rear baffle lock nut threads to your camera sensor, the same spacing used without the reducer. This generous distance provides ample room to install a full imaging train, including an off-axis guider (OAG), a filter wheel, and any necessary adapters, without running out of space.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this reducer work with a full-frame camera on my EdgeHD 9.25\"?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer is designed with a \u003cstrong\u003e60mm clear aperture\u003c\/strong\u003e and produces a \u003cstrong\u003e42mm image circle\u003c\/strong\u003e. Celestron designed it for use with larger (full frame) sensors. A full-frame diagonal (about 43mm) is slightly larger than the 42mm circle, so expect some light falloff in the extreme corners.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs it difficult to attach the .7x Reducer to the EdgeHD 9.25\" telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, it's straightforward. The reducer threads directly onto the large 3.25\" threaded baffle tube port on the rear cell of the EdgeHD 9.25\". This provides a secure, flexure-free connection that is essential for sharp imaging.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e4-Element\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompression Factor\u003c\/td\u003e\n\u003ctd\u003e0.7x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptimal Back Focus\u003c\/td\u003e\n\u003ctd\u003e146mm (5.75\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e42mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e60mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGlass Type\u003c\/td\u003e\n\u003ctd\u003eLanthanum Elements\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Coatings\u003c\/td\u003e\n\u003ctd\u003eFully Multi-Coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHousing\u003c\/td\u003e\n\u003ctd\u003eMachined Aluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e2.3 lbs (1.47 kg)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003eCelestron EdgeHD female\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned For\u003c\/td\u003e\n\u003ctd\u003eCelestron EdgeHD 9.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eReducer Lens .7x for EdgeHD 9.25\"\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eThreaded Metal Dust Cap (Front)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eThreaded Metal Dust Cap (Rear)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.celestron.com\/pages\/drivers-and-software\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Celestron Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Limited Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967146029341,"sku":"CEL-94245","price":610.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-Reducer-Lens-7x-EdgeHD-925-94245-1__58642.1594230249.1280.1280.jpg?v=1684337176"},{"product_id":"explore-scientific-2-field-flattener","title":"Explore Scientific Field Flattener for f\/5 to f\/7 Refractors","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eCorrects field curvature for pinpoint stars edge-to-edge\u003c\/li\u003e\n\u003cli\u003eOptimized for refractor telescopes with f\/5 to f\/7 focal ratios\u003c\/li\u003e\n\u003cli\u003eRequires a precise 55mm (+\/- 2mm) back focus distance\u003c\/li\u003e\n\u003cli\u003eDesigned for astrophotography use only\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eExplore Scientific Field Flattener for f\/5 to f\/7 Refractors\u003c\/h2\u003e\n\u003cp\u003eFor refractor telescopes with focal ratios from f\/5 to f\/7, the Explore Scientific Field Flattener corrects the inherent field curvature that causes elongated stars at the edge of an image. This photographic-only accessory produces a flat, sharp field across large sensors by requiring a precise 55mm distance from its mounting flange to your camera's sensor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003ePinpoint Stars Edge-to-Edge in f\/5 to f\/7 Refractors\u003c\/h3\u003e\n\u003cp\u003eFast refractors produce stunning, high-contrast images, but their optics naturally create a curved focal plane. This results in coma, an aberration that smears stars near the corners of your photograph into comet-like shapes. The effect becomes more pronounced with larger camera sensors and faster focal ratios.\u003c\/p\u003e\n\u003cp\u003eThis Explore Scientific Field Flattener is optically matched to correct this specific aberration in refractors operating between f\/5 and f\/7. By inserting it into the optical train, you ensure that stars remain tight, round points from the center of the frame to the extreme corners, preserving the full resolution of your telescope and camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAchieving the Critical 55mm Back Focus\u003c\/h3\u003e\n\u003cp\u003eA field flattener's correction depends entirely on maintaining a specific distance to the camera sensor. This unit requires a rigid 55mm of back focus, with a tight tolerance of only +\/- 2mm, measured from the rear flange of the flattener to your camera's focal plane.\u003c\/p\u003e\n\u003cp\u003eThis 55mm spacing is standard for DSLR cameras using a T-ring, but will require a combination of extension tubes for most dedicated astronomy cameras. Achieving this precise distance is non-negotiable for optimal results; incorrect spacing will lead to over- or under-correction. Note that this is a 1.0x flattener, designed only to correct aberrations without reducing your telescope's focal length.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is a field flattener and why do I need one for my Explore Scientific ED80 f\/6 refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA field flattener is an optical corrector that compensates for the natural curvature of a refractor's focal plane. An f\/6 refractor like the ED80 is fast enough to show noticeable star elongation (coma) in the corners of an image, especially with a larger sensor. The Explore Scientific Field Flattener is designed for the f\/5 to f\/7 range, making it a perfect match to ensure your astrophotos have sharp, pinpoint stars across the entire frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I get the correct 55mm spacing for the Field Flattener when imaging the Andromeda Galaxy (M31) with my ZWO ASI533MC Pro?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou must create a total distance of exactly 55mm between the flattener's rear flange and the ASI533MC Pro's sensor. The camera itself has a specific back focus distance (check its manual, often 6.5mm or 17.5mm depending on configuration). You will need to use a combination of threaded extension tubes (spacers) to make up the remaining distance to reach 55mm. For example, if your camera has 17.5mm of back focus, you would need 37.5mm of extensions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this Field Flattener work on my f\/8 refractor or my f\/4 Newtonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. This flattener is optically designed specifically for \u003cstrong\u003erefractor telescopes\u003c\/strong\u003e in the \u003cstrong\u003ef\/5 to f\/7\u003c\/strong\u003e focal ratio range. Using it outside this designated range or with a different telescope design like a Newtonian will result in poor optical correction and unsatisfactory star shapes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Explore Scientific Field Flattener for visual observing with an eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this is a photographic-only accessory. It is not designed to work with an eyepiece and will not allow you to reach focus for visual use. It must be threaded directly into an imaging train with a camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eMy stars are still elongated after installing the Field Flattener. What's wrong?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe most common cause of poor correction is incorrect back focus. The required 55mm distance has a very small tolerance of only +\/- 2mm. Even a small error in your spacer calculations can degrade the result. Meticulously check the back focus of your camera and the length of all extensions in your imaging train to ensure the total distance is exactly 55mm.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes this accessory change the focal length of my telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. This is a 1.0x field flattener, not a focal reducer. It is engineered to correct optical aberrations without altering the native focal length or focal ratio of your telescope.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e811803034297\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Compatibility\u003c\/td\u003e\n\u003ctd\u003eRefractors\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio Range\u003c\/td\u003e\n\u003ctd\u003ef\/5 to f\/7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired Back Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (+\/- 2mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e1.0x (Flattener only)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIntended Use\u003c\/td\u003e\n\u003ctd\u003ePhotographic Only\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eField Flattener for f\/5 to f\/7 Refractors\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/explore-scientific-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eExplore Scientific Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44967198687517,"sku":"ES-FF2F5\/F7","price":196.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/ExploreScientific-Field-Flattener-f-5-to-f-7-1_d768abfe-a4e9-4838-ac0f-dc68f35b60f2.jpg?v=1789061650"},{"product_id":"explore-scientific-3-field-flattener-7x-focal-reducer","title":"Explore Scientific 3\" Field Flattener .7x Focal Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal ratio by a factor of 0.7x for wider fields and shorter exposures\u003c\/li\u003e\n\u003cli\u003eFunctions as a field flattener to correct edge-of-field aberrations\u003c\/li\u003e\n\u003cli\u003eEngineered for Explore Scientific 127mm and 152mm APO refractors\u003c\/li\u003e\n\u003cli\u003eRequires a precise 55mm back focus from the rear of the unit\u003c\/li\u003e\n\u003cli\u003eFeatures fully multi-coated optics for maximum light transmission\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eExplore Scientific 3\" Field Flattener .7x Focal Reducer\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 3\" Field Flattener and 0.7x \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003eFocal Reducer\u003c\/a\u003e is an essential imaging accessory that corrects optical aberrations while simultaneously speeding up your photographic system. Designed for Explore Scientific's 127mm and 152mm refracting telescopes, it transforms a native f\/8 instrument into a faster f\/5.6 imaging platform, reducing exposure times by nearly 50%. This corrector provides a critical 55mm of back focus and is confirmed to deliver excellent results with \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e operating at both f\/8 and f\/7.5.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eDual-Function Optics: A 0.7x Reducer for Faster Imaging\u003c\/h3\u003e\n\u003cp\u003eThis accessory performs two critical roles for the astrophotographer. As a focal reducer, its 0.7x magnification factor makes your telescope optically \"faster,\" widening your field of view and concentrating starlight onto your camera's sensor. This allows you to capture faint details with significantly shorter exposure times and fit larger deep-sky objects, like the Andromeda Galaxy (M31), into a single frame.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWider Field of View:\u003c\/strong\u003e Capture expansive nebulae and large star clusters without creating a mosaic.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrighter Images:\u003c\/strong\u003e By reducing the f-ratio, the reducer increases image brightness, improving your signal-to-noise ratio in less time.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFully Multi-Coated:\u003c\/strong\u003e High-transmission coatings on all optical surfaces ensure that the maximum amount of light reaches your sensor, preserving contrast and detail.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eTack-Sharp Stars to the Edge of the Field\u003c\/h3\u003e\n\u003cp\u003eRefractor telescopes naturally create a curved focal plane, which means that while the center of your image may be in perfect focus, stars towards the corners can appear elongated and soft. This 3\" field flattener is engineered to counteract this effect, producing a flat, corrected field of view that is essential for modern high-resolution sensors. The result is crisp, pinpoint stars from one edge of the frame to the other.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAchieving 55mm Back Focus with Explore Scientific Focusers\u003c\/h3\u003e\n\u003cp\u003eProper spacing is the most critical element for any flattener or reducer. This unit requires a precise sensor distance of 55mm, measured from the rear face of the reducer housing. The M42x0.75 T-thread adapter takes up 3mm of this distance, meaning your camera sensor must be placed exactly 52mm from the shoulder of the \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-adapter\u003c\/a\u003e. This accessory includes an adapter for the Explore Scientific 2-inch rack-and-pinion focuser, but connecting to the 2.5-hex focuser on the 127mm APO requires a separate adapter (part #510366).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the correct back focus for the ES 3\" 0.7x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe required back focus is \u003cstrong\u003e55mm\u003c\/strong\u003e, measured from the rear flange of the reducer unit itself. The standard M42x0.75 T-thread adapter uses 3mm of this distance, leaving you with a \u003cstrong\u003e52mm\u003c\/strong\u003e spacing requirement between the adapter and your camera's sensor. This is a common distance for DSLR cameras with a standard T-ring.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich Explore Scientific telescopes are compatible with this 3\" 0.7x reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis reducer\/flattener is specifically recommended for the Explore Scientific \u003cstrong\u003e127mm and 152mm APO triplet refractors\u003c\/strong\u003e. It is not designed for use with their doublet refractors. It has been tested and confirmed to perform exceptionally well with optical systems at both f\/8 and f\/7.5.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need a special adapter for my Explore Scientific 127mm APO refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, most likely. The ES 127mm \u003ca href=\"\/en-int\/collections\/apochromatic-refractors\"\u003eAPO refractor\u003c\/a\u003e typically ships with a 2.5-hex focuser. To connect this 3\" reducer, you must purchase the specific adapter, part number \u003cstrong\u003e510366\u003c\/strong\u003e. The reducer does include an adapter for the Explore Scientific 2-inch rack-and-pinion focuser, but this is not the standard focuser on the 127mm model.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the 0.7x reduction help when imaging the North American Nebula (NGC 7000)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 0.7x reduction provides a wider field of view, which is essential for framing large emission nebulae like the North American Nebula (NGC 7000) in their entirety, especially with larger sensors. It also makes your telescope faster (e.g., f\/8 becomes f\/5.6), significantly reducing the exposure time needed to capture the faint, expansive clouds of hydrogen-alpha gas.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the difference between a focal reducer and a field flattener?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis accessory combines both functions, but they solve different problems:\n\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eA \u003cstrong\u003eFocal Reducer\u003c\/strong\u003e shortens the effective focal length of your telescope. This makes the image brighter and the field of view wider.\u003c\/li\u003e\n\u003cli\u003eA \u003cstrong\u003eField Flattener\u003c\/strong\u003e corrects for the natural curvature of a refractor's focal plane, ensuring stars are sharp and round across the entire image, not just in the center.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Explore Scientific 3\" reducer for visual observing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis device is designed and optimized specifically for astrophotography. Its optical corrections are calculated to produce a flat field on a camera sensor at a precise 55mm distance. It is not intended for visual use with an \u003ca href=\"\/en-int\/collections\/eyepieces\"\u003eeyepiece\u003c\/a\u003e and will not perform as a standard visual accessory.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eAccessory Type\u003c\/td\u003e\n\u003ctd\u003eField Flattener \u0026amp; Focal Reducer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBarrel Size\u003c\/td\u003e\n\u003ctd\u003e3\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Reduction\u003c\/td\u003e\n\u003ctd\u003e0.7x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired Back Focus\u003c\/td\u003e\n\u003ctd\u003e55mm from rear face of unit\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection\u003c\/td\u003e\n\u003ctd\u003eM42x0.75 T-Thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRecommended Telescopes\u003c\/td\u003e\n\u003ctd\u003eExplore Scientific 127mm \u0026amp; 152mm APOs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRecommended F-Ratios\u003c\/td\u003e\n\u003ctd\u003ef\/7.5 to f\/8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptics\u003c\/td\u003e\n\u003ctd\u003eFully Multi-Coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e812257014408\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e635 g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eThreaded adapter for ES 2\" rack-and-pinion focuser (2.5\" hex: adapter 510366)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e3in field flattener\/0.7x reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003ethreaded adapter for the ES 2in rack-and-pinion focuser\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/explore-scientific-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eExplore Scientific Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44967198720285,"sku":"ES-FFFR507X-00","price":559.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-3-inch-Field-Flattener-7x-Focal-Reducer-FFFR507X-00-FFFR507X-00-1__88587.1594240338.1280.1280.jpg?v=1684338681"},{"product_id":"william-optics-adjustable-flat61-for-z61","title":"William Optics Adjustable Flat61 for Z61","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e1.0x Flattener Power\u003c\/li\u003e\n\u003cli\u003eDesigned for William Optics Zenithstar 61\u003c\/li\u003e\n\u003cli\u003eFull-Frame Sensor Coverage\u003c\/li\u003e\n\u003cli\u003eAdjustable Back Focus Mechanism\u003c\/li\u003e\n\u003cli\u003eM54 Telescope Thread \u0026amp; M48 Camera Thread\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eWilliam Optics Adjustable Flat61 for Z61\u003c\/h2\u003e\n\u003cp\u003eThe William Optics Adjustable Flat61 is the definitive imaging accessory for the Zenithstar 61, delivering edge-to-edge pinpoint stars on sensors up to full-frame format at a native 1.0x power. Its 2-element, 2-group optical design corrects the field curvature inherent in a fast \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractor\u003c\/a\u003e, connecting to the telescope via a rigid M54 x 0.75 thread and to your camera with a standard M48 x 0.75 T-mount. Weighing just 272.8 g, the unit's optical path consists of the 39.5 mm \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003eflattener\u003c\/a\u003e body and a 19 mm \u003ca href=\"\/en-int\/collections\/rotators-and-tilt-adjusters\"\u003erotator\u003c\/a\u003e and adapter section, engineered for precise spacing and image composition.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e1.0x Power for Full-Frame Correction with the Zenithstar 61\u003c\/h3\u003e\n\u003cp\u003eThis flattener corrects field curvature without altering the native focal length or focal ratio of your Z61 telescope. The 1.0x magnification ensures the field of view you framed visually is the same one you capture, preserving the telescope's original optical characteristics. The 2-element in 2-group lens design is optimized specifically for the Z61's optics, providing a flat, corrected image circle large enough to accommodate full-frame (36x24mm) sensors without vignetting or distorted stars at the corners.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eM54 Telescope Connection \u0026amp; M48 Camera Interface\u003c\/h3\u003e\n\u003cp\u003eThe Flat61A attaches to the Z61 \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e using a robust M54 x 0.75 threaded connection, eliminating any potential for tilt or flex that can occur with simple compression fittings. The camera side features the astrophotography standard M48 x 0.75 thread, providing a wide, secure aperture for filters and direct connection to dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e and a broad range of DSLR\/mirrorless T-mounts. The integrated rotator allows you to frame your target perfectly without loosening any threaded connections, maintaining rigid alignment throughout your imaging session.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAdjustable Back Focus for Edge-to-Edge Sharpness\u003c\/h3\u003e\n\u003cp\u003eAchieving a perfectly flat field requires precise spacing between the flattener's rear element and the camera sensor. While fixed-length flatteners work well with a specific camera setup, the Adjustable Flat61 acknowledges that \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e, \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e, or different \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e thicknesses can alter this critical distance. This unit's key feature is its ability to be fine-tuned, allowing you to dial in the exact back focus required by your unique imaging train to guarantee sharp stars across the entire frame, not just in the center.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the purpose of the William Optics Adjustable Flat61?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Flat61A is an optical corrector designed specifically for the William Optics Zenithstar 61 refractor. It flattens the curved focal plane of the telescope, ensuring that stars are sharp and pinpoint across the entire field of view, from the center to the corners of your camera sensor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect the Flat61A to my Z61 and camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe flattener connects directly to the Z61 focuser's drawtube via a secure \u003cstrong\u003eM54 x 0.75 thread\u003c\/strong\u003e. The camera side features a standard \u003cstrong\u003eM48 x 0.75 thread\u003c\/strong\u003e, which is compatible with most dedicated astronomy cameras, filter wheels, and T-mounts for DSLR and mirrorless cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is an adjustable flattener like the Flat61A better than a fixed one?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAn adjustable flattener provides the flexibility to achieve perfect back focus with various imaging setups. Different cameras, filter thicknesses, and adapters can slightly change the ideal spacing. The Flat61A allows you to fine-tune this distance, ensuring optimal optical correction regardless of the specific components in your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Flat61A change the focal length of my Zenithstar 61?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The William Optics Flat61A is a \u003cstrong\u003e1.0x flattener\u003c\/strong\u003e, meaning it does not reduce or extend the telescope's focal length. It corrects for optical aberrations while preserving the Z61's native field of view and f-ratio.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the William Optics Flat61A with a full-frame camera like the Sony A7 series on my Z61?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The Flat61A is explicitly designed to provide a corrected image circle for \u003cstrong\u003eFull Frame\u003c\/strong\u003e sensors. With the appropriate M48 T-mount for Sony E-mount cameras (listed in the supported T-mounts), you can achieve a flat field with your Sony A7 series camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Flat61A provide a flat field for imaging the Andromeda Galaxy (M31) with my Z61 and an APS-C camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. The flattener is designed for sensors up to full-frame, so it will provide excellent correction for smaller \u003cstrong\u003eAPS-C\u003c\/strong\u003e and \u003cstrong\u003eM4\/3\u003c\/strong\u003e sensors. It will ensure that all the stars across the vast expanse of the Andromeda Galaxy (M31) are rendered as sharp points.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eFlattener Power\u003c\/td\u003e\n\u003ctd\u003e1.0x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e2 Elements in 2 Groups\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Format Support\u003c\/td\u003e\n\u003ctd\u003eFull Frame, APS-C, M4\/3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Connection\u003c\/td\u003e\n\u003ctd\u003eM54 x 0.75 x 5 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection\u003c\/td\u003e\n\u003ctd\u003eM48 x 0.75 x 4 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Path Components\u003c\/td\u003e\n\u003ctd\u003eFlattener 39.5 mm + Rotator\/Adapter 19 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSupported T-Mounts\u003c\/td\u003e\n\u003ctd\u003eCanon EF, RF; Nikon F, Z; Sony E; Pentax K; MFT (M4\/3); FUJI X\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e272.8 g (0.60 lbs)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e43 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eWilliam Optics ZenithStar 61\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e1x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eWilliam Optics Adjustable Flat61 for Z61\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967219822877,"sku":"WO-P-FLAT61A","price":365.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/William-Optics-Adjustable-Flat61-for-Z61-P-FLAT61A-1__32465.1596133236.1280.1280.jpg?v=1684339110"},{"product_id":"william-optics-adjustable-reducer-flattener-flat61r-for-z61","title":"William Optics Adjustable Reducer Flattener Flat61R for Z61","description":"\u003cul\u003e\n\t\u003cli\u003eAdjustable reducer and field flattener for William Optics Z61 telescope\u003c\/li\u003e\n\t\u003cli\u003eImproves image sharpness and reduces distortion\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\t\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cul class=\"tabs-content\"\u003e\n\t\u003cli class=\"active\"\u003e\n\t\t\u003cp\u003e\nThe William Optics Adjustable \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003eReducer Flattener\u003c\/a\u003e Flat61R is an essential accessory for the William Optics Z61 telescope. This adjustable reducer and field flattener enhances image sharpness and reduces distortion, ensuring high-quality astrophotography results.\n\t\t\u003c\/p\u003e\n\t\t\u003cdiv class=\"warning\"\u003e\n\t\t\t\u003cimg alt=\"Disclaimer\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/warning-logo.svg?v=1714663206\" width=\"25px\"\u003e\n\t\t\t\u003cp\u003e\nSpecifically designed for the William Optics Z61 telescope.\n\t\t\t\u003c\/p\u003e\n\t\t\u003c\/div\u003e\n\t\t\n\t\t\u003cdiv\u003e\n\t\t\t\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\t\t\t\u003chr\u003e\n\t\t\t\u003cdiv class=\"two-columns-section\"\u003e\n\t\t\t\t\u003cdiv class=\"text-side-2\"\u003e\n\t\t\t\t\t\u003cp\u003e\nThe Flat61R is designed to perfectly fit the William Optics Z61 telescope. It ensures a seamless connection, enhancing the optical performance of your telescope.\n\t\t\t\t\t\u003c\/p\u003e\n\t\t\t\t\u003c\/div\u003e\n\t\t\t\t\u003cdiv class=\"image-side-2\" data-mce-style=\"text-align: start;\" style=\"text-align: start;\"\u003e\n\t\t\t\t\t\u003cimg alt=\"William Optics Adjustable Reducer Flattener Flat61R for Z61\" src=\"https:\/\/davidastro.com\/cdn\/shop\/files\/William-Optics-Adjustable-Reducer-Flattener-Flat61R-for-Z61-P-FLAT61R-2__19145.1596133238.1280.1280_832x832.jpg?v=1684339301\" style=\"margin-bottom: 16px; float: none;\"\u003e\n\t\t\t\t\u003c\/div\u003e\n\t\t\t\u003c\/div\u003e\n\n\t\t\t\u003cdiv data-mce-style=\"backgroundcolor: #0a0001; border-radius: 5px;\" style=\"background-color: #0a0001; border-radius: 5px;\"\u003e\n\t\t\t\t\u003ch3 style=\"color: white!important;\"\u003eEnhanced Image Quality\u003c\/h3\u003e\n\t\t\t\t\u003chr\u003e\n\t\t\t\t\u003cdiv class=\"two-columns-section\"\u003e\n\t\t\t\t\t\u003cdiv class=\"image-side-2\" data-mce-style=\"text-align: start;\" style=\"text-align: start;\"\u003e\n\t\t\t\t\t\t\u003cimg alt=\"William Optics Adjustable Reducer Flattener Flat61R for Z61\" src=\"https:\/\/davidastro.com\/cdn\/shop\/files\/William-Optics-Adjustable-Reducer-Flattener-Flat61R-for-Z61-P-FLAT61R-8__83135.1596133238.1280.1280_832x832.jpg?v=1684339311\" style=\"margin-bottom: 16px; float: none;\"\u003e\n\t\t\t\t\t\u003c\/div\u003e\n\t\t\t\t\t\u003cdiv class=\"text-side-2\"\u003e\n\t\t\t\t\t\t\u003cp style=\"color: white!important;\"\u003e\nThe adjustable reducer flattener improves image sharpness across the field, reducing optical aberrations and ensuring crisp, clear images of celestial objects.\n\t\t\t\t\t\t\u003c\/p\u003e\n\t\t\t\t\t\u003c\/div\u003e\n\t\t\t\t\u003c\/div\u003e\n\t\t\t\u003c\/div\u003e\n\t\t\u003c\/div\u003e\n\n\t\t\u003ch3\u003eAdjustable Design\u003c\/h3\u003e\n\t\t\u003chr\u003e\n\t\t\u003cp\u003e\nThe Flat61R features an adjustable design, allowing users to fine-tune the distance to the camera sensor for optimal performance, ensuring perfect star shapes across the entire image.\n\t\t\u003c\/p\u003e\n\t\t\n\t\t\u003ch3\u003eDurable Construction\u003c\/h3\u003e\n\t\t\u003chr\u003e\n\t\t\u003cp\u003e\nMade from high-quality materials, such as anodized aluminum, the Flat61R is built to last, providing durability and stability for all your astrophotography needs.\n\t\t\u003c\/p\u003e\n\n\t\t\u003ch3\u003ePrecision Engineering\u003c\/h3\u003e\n\t\t\u003chr\u003e\n\t\t\u003cp\u003e\nThe Flat61R is engineered with precision to ensure a tight and secure fit, minimizing any unwanted movement or vibrations and enhancing overall image quality.\n\t\t\u003c\/p\u003e\n\n\t\t\u003ch3\u003eEase of Use\u003c\/h3\u003e\n\t\t\u003chr\u003e\n\t\t\u003cp\u003e\nDesigned for easy attachment and detachment, the Flat61R allows users to quickly set up or dismantle their equipment as needed, making it convenient for field use.\n\t\t\u003c\/p\u003e\n\n\t\t\u003ch3\u003eVersatility\u003c\/h3\u003e\n\t\t\u003chr\u003e\n\t\t\u003cp\u003e\nBuilt for astrophotography with the Z61, the Flat61R provides the necessary optical enhancements for detailed and high-quality imaging.\n\t\t\u003c\/p\u003e\n\t\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967220019485,"sku":"WO-P-FLAT61R","price":389.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/William-Optics-Adjustable-Reducer-Flattener-Flat61R-for-Z61-P-FLAT61R-1__95363.1596133238.1280.1280.jpg?v=1684339299"},{"product_id":"william-optics-flattener-68iii","title":"William Optics Flattener 68III","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e1.0x Flattener Power preserves native focal length\u003c\/li\u003e\n\u003cli\u003eCorrects field curvature for Full Frame sensors\u003c\/li\u003e\n\u003cli\u003eDesigned for William Optics FLT132, GT102, and GT153 refractors\u003c\/li\u003e\n\u003cli\u003eConnects via a robust M92 telescope-side thread\u003c\/li\u003e\n\u003cli\u003eFeatures a standard M48 camera-side thread to prevent vignetting\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eWilliam Optics Flattener 68III\u003c\/h2\u003e\n\u003cp\u003eThe William Optics Flattener 68III is an essential imaging accessory designed to deliver perfectly flat fields across full-frame sensors without altering your telescope's native focal length. This 1.0x flattener connects directly to the \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e of premier William Optics \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e like the FLT132, GT102, and GT153 via a secure M92 x 1 thread. Its efficient 2-element optical design corrects for field curvature, ensuring pinpoint stars from the center to the corners of your frame, while the M48 camera connection minimizes vignetting for modern DSLR and dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e1.0x Flattening: Edge-to-Edge Correction for Full-Frame Sensors\u003c\/h3\u003e\n\u003cp\u003eThis flattener is engineered for the imaging purist. With a 1.0x power factor, it maintains your telescope's exact focal length and f-ratio, preserving the original image scale for maximum resolution on planetary and small deep-sky targets. The optical system, comprised of 2 elements in 2 groups, is fully multi-coated to ensure high light transmission and contrast, turning the curved focal plane of a fast refractor into a flat, corrected surface ready for large sensors.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFull Frame Illumination:\u003c\/strong\u003e The image circle is 44.4mm on the FLT132 and 43.4mm on the FLT91 with back adapter, making it ideal for full-frame (24x36mm), APS-C, and M4\/3 formats.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePinpoint Stars:\u003c\/strong\u003e Eliminates the elongated, comatic stars typically seen at the edges of uncorrected images, producing sharp, round stars across your entire field of view.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePreserves Native Scale:\u003c\/strong\u003e Unlike a reducer, this flattener allows you to image at your telescope's maximum magnification and resolution, ideal for detailed studies of galaxies and nebulae.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eM92 Interface: Optimized for William Optics FLT and GT Refractors\u003c\/h3\u003e\n\u003cp\u003eThe Flattener 68III creates a seamless, rigid connection with specific William Optics telescopes. It threads directly onto the M92 drawtube of the FLT132, GT102, and GT153 refractors, ensuring perfect alignment and eliminating any potential for flexure in the imaging train. This robust mechanical design is critical for supporting heavier camera packages.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTelescope Connection:\u003c\/strong\u003e The M92 x 1 thread provides a secure, direct-fit attachment to compatible William Optics focusers.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCamera Connection:\u003c\/strong\u003e A standard M48 x 0.75 thread on the camera side offers a wider aperture than older T2 (M42) threads, preventing vignetting on full-frame sensors.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBroad Camera Support:\u003c\/strong\u003e Compatible with standard M48 T-rings for Canon, Nikon, Sony, Pentax, MFT, and Fuji camera systems.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 64.5mm Optical Path with Precision Back-Focus Adjustment\u003c\/h3\u003e\n\u003cp\u003eAchieving perfect sensor-to-flattener spacing is critical for optimal correction, and the Flattener 68III is built with this in mind. The unit is adjustable, allowing you to precisely dial in the required back focus for your specific camera and filter setup. This fine-tuning capability ensures you can achieve the sharpest possible stars across the entire field, regardless of minor variations in your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the primary function of the William Optics Flattener 68III?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Flattener 68III is an optical corrector designed to eliminate field curvature in refractor telescopes. It ensures that stars are sharp and pinpoint not just in the center of the image, but all the way to the corners. As a \u003cstrong\u003e1.0x flattener\u003c\/strong\u003e, it accomplishes this without changing the telescope's native focal length or f-ratio.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich telescopes is the Flattener 68III compatible with?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFlattener 68III back focus settings are available for the \u003ca href=\"\/en-int\/products\/william-optics-fluorostar-91\"\u003eFluorostar 91\u003c\/a\u003e and Gran Turismo 81 (each with a back adapter), \u003ca href=\"\/en-int\/products\/william-optics-fluorostar-120\"\u003eFluorostar 120\u003c\/a\u003e, \u003ca href=\"\/en-int\/products\/william-optics-fluorostar-156\"\u003eFluorostar 156\u003c\/a\u003e and Zenithstar 126, as well as these models:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/en-int\/products\/william-optics-fluorostar-132\"\u003eFluorostar 132\u003c\/a\u003e (FLT132)\u003c\/li\u003e\n\u003cli\u003eGran Turismo 102 (GT102)\u003c\/li\u003e\n\u003cli\u003eGran Turismo 153 (GT153)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Flattener 68III perform with a full-frame camera like a Sony A7 on the GT102?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt's an excellent match. The Flattener 68III is designed to correct the entire field of a full-frame sensor. When paired with a GT102, you can expect sharp, round stars across the entire 24x36mm sensor of a Sony A7-series camera, with minimal vignetting thanks to the M48 camera connection.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy should I choose this 1.0x Flattener 68III instead of a reducer\/flattener?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eChoose the 1.0x Flattener 68III when your primary goal is \u003cstrong\u003emaximum image resolution and scale\u003c\/strong\u003e. A \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003ereducer\/flattener\u003c\/a\u003e makes your telescope \"faster\" and provides a wider field of view, but it shrinks the image. For detailed work on smaller galaxies or planetary nebulae where every bit of focal length matters, a 1.0x flattener is the superior choice.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the \"adjustable\" feature of the Flattener 68III do?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe adjustable design allows you to make micro-adjustments to the back focus distance—the spacing between the flattener's rear lens and your camera sensor. This is crucial for achieving perfect corner-to-corner star sharpness, as it lets you compensate for the exact thickness of your adapters, \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e, or \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Flattener 68III work for imaging the full Andromeda Galaxy (M31) with an FLT132?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile the Flattener 68III will provide a perfectly corrected field, an FLT132 at its native focal length may be too magnified to capture the entire Andromeda Galaxy (M31) in a single frame, even with a full-frame sensor. For a target of that size with that telescope, a reducer\/flattener would be a better choice to achieve a wider field of view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower\u003c\/td\u003e\n\u003ctd\u003e1.0 x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e2 Elements in 2 Groups\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSupported Sensor Formats\u003c\/td\u003e\n\u003ctd\u003eFull Frame, APS-C, M4\/3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Thread\u003c\/td\u003e\n\u003ctd\u003eM92 x 1 x 6.5 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Thread\u003c\/td\u003e\n\u003ctd\u003eM48 x 0.75 x 4 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003e64.5 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Brand Support\u003c\/td\u003e\n\u003ctd\u003eCanon EF, RF, Nikon F, Z, Sony E, Pentax K, MFT (M4\/3), FUJI X\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e718.2 g \/ 1.58 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e44.4 mm (FLT132), 43.4 mm (FLT91 with back extender)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired back focus\u003c\/td\u003e\n\u003ctd\u003e62.7 mm (FLT132), 65.7 mm (FLT120), 57.6 mm (FLT156)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eFLT132, GT102, GT153, FLT120, FLT156\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eWilliam Optics Flattener 68III\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967220117789,"sku":"WO-P-FLAT68III","price":1033.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/William-Optics-Flattener-68III-P-FLAT68III-1__37693.1596133239.1280.1280.jpg?v=1684339133"},{"product_id":"william-optics-adjustable-flat6aiii","title":"William Optics Adjustable Flat6AIII","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e0.8x Focal Reducer \u0026amp; Field Flattener\u003c\/li\u003e\n\u003cli\u003eOptimized for GT71, GT81, Z81 \u0026amp; Z103 Refractors\u003c\/li\u003e\n\u003cli\u003eIlluminates Full-Frame Sensors\u003c\/li\u003e\n\u003cli\u003eAdjustable Back Focus Mechanism\u003c\/li\u003e\n\u003cli\u003eM63 Telescope-Side Thread\u003c\/li\u003e\n\u003cli\u003eM48 Camera-Side Thread with Filter Slot\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section-center\"\u003e\n      \u003ch2\u003eWilliam Optics Adjustable Flat6AIII 0.8x Reducer \u0026amp; Flattener\u003c\/h2\u003e\n      \u003cp\u003eThe William Optics Adjustable Flat6AIII is a 0.8x reducer and \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003eflattener\u003c\/a\u003e engineered specifically to convert William Optics GT71, GT81, Z81, and Z103 \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e into flat-field \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrographs\u003c\/a\u003e. Its 3-element apochromatic optical design uses Ohara glass to correct for field curvature across 97% of a full-frame sensor, connecting directly to the telescope via an M63 thread and to your camera with a standard M48 T-mount.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003e0.8x Reduction and 97% Full-Frame Illumination\u003c\/h3\u003e\n      \u003cp\u003eBy reducing your telescope's focal ratio by a factor of 0.8x, the Flat6AIII significantly shortens required exposure times and expands your field of view. This transforms a GT81 from f\/5.9 to a faster f\/4.7 system, allowing you to capture faint nebulosity in less time and frame larger targets like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000). The optical design provides excellent illumination and pinpoint stars across 97% of a full-frame sensor's \u003ca href=\"\/en-int\/collections\/diagonals\"\u003ediagonal\u003c\/a\u003e.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eAPO Triplet Optics: A 3-Element Ohara Glass Design\u003c\/h3\u003e\n      \u003cp\u003eThe Flat6AIII employs a 3-element apochromatic (APO) lens design constructed from premium Ohara glass. This triplet configuration, combined with full multi-coatings, ensures high-contrast images free of distracting chromatic aberration. Where simpler flatteners can introduce bloated or discolored stars at the edge of the field, the Flat6AIII maintains sharp, color-pure stars right to the corners of your frame, preserving the optical integrity of your William Optics refractor.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n  \n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eM63 Direct-Thread Integration for 4 William Optics Refractors\u003c\/h3\u003e\n      \u003cp\u003eThis flattener attaches directly to the \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e drawtube using a robust M63 thread, creating a solid, flex-free imaging train. This direct connection is superior to standard 2\" nosepiece adapters, which can introduce tilt. The body of the Flat6AIII is adjustable to set the precise back focus for your specific telescope, and an integrated M48 filter slot behind the camera threads allows for the easy installation of 2\" filters without adding extra accessories.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhich William Optics telescopes is the Flat6AIII compatible with?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe William Optics Flat6AIII is specifically designed and optimized for four refractors: the \u003cstrong\u003eGT71\u003c\/strong\u003e, \u003cstrong\u003eGT81\u003c\/strong\u003e, \u003cstrong\u003eZ81\u003c\/strong\u003e, and \u003cstrong\u003eZ103\u003c\/strong\u003e. It connects via a direct M63 thread on these models.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 0.8x reduction of the Flat6AIII benefit my imaging with a GT81?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe 0.8x reduction makes your telescope \"faster,\" meaning it gathers light more quickly. On a GT81 (f\/5.9), the Flat6AIII creates an f\/4.7 imaging system. This reduces your required exposure time by about 36%, allowing you to collect more data in a single night. It also provides a wider field of view to better frame large deep-sky objects.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use a full-frame DSLR like a Canon EOS Ra with the Flat6AIII?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eYes. The Flat6AIII is designed to fully illuminate and correct for full-frame sensors up to 44mm. You will need the appropriate M48 \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e for your camera mount (e.g., Canon RF) to connect it to the flattener's M48 threads.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I attach the Flat6AIII to my telescope?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Flat6AIII threads directly onto the focuser. You will first need to unthread and remove the standard 2\" \u003ca href=\"\/en-int\/collections\/visual-adapters\"\u003eeyepiece holder\u003c\/a\u003e from your telescope's focuser. The flattener's M63 threads then screw directly onto the focuser drawtube for a secure, tilt-free connection.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2\" filters with the William Optics Flat6AIII?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eYes. The Flat6AIII has an integrated M48 x 0.75 filter thread just inside the camera-side connection. This allows you to thread in any standard 2\" astronomy filter (which uses M48 threads) for light pollution reduction or narrowband imaging.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"adjustable back focus\" mean on the Flat6AIII?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe body of the William Optics Flat6AIII can be extended or retracted to fine-tune the distance between the flattener's optics and your camera sensor. Each compatible telescope model requires a slightly different spacing for a perfectly flat field. This adjustability ensures you can achieve optimal optical correction without needing to add or remove spacers.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n\u003ctd\u003eFlattener Power\u003c\/td\u003e\n\u003ctd\u003e0.8 x\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eLens Design\u003c\/td\u003e\n\u003ctd\u003e3 Groups, 3 Elements\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eCamera Format Support\u003c\/td\u003e\n\u003ctd\u003eFull Frame, APS-C, M4\/3\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eTelescope Connection\u003c\/td\u003e\n\u003ctd\u003eM63 x 1 x 6 mm Thread\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eCamera Connection\u003c\/td\u003e\n\u003ctd\u003eM48 x 0.75 x 4 mm T-Mount Thread\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eCompatible T-Mounts\u003c\/td\u003e\n\u003ctd\u003eCanon EF, RF, Nikon F, Z, Sony E, Pentax K, MFT (M4\/3), FUJI X\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003e61.5 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e519.4 g \/ 1.15 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e44.4 mm (GT71, GT81), 44.3 mm (Z81), 43.1 mm (Z103)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired back focus\u003c\/td\u003e\n\u003ctd\u003e64.1 mm (GT71), 62.1 mm (GT81), 60.2 mm (Z81), 57.5 mm (Z103)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eGT71, GT81, Z81, Z103\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e0.8x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eWilliam Optics Adjustable Flat6AIII\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967221002525,"sku":"WO-P-FLAT6AIII","price":352.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/William-Optics-FLAT6AIII__75538.1675887359.1280.1280.jpg?v=1684339316"},{"product_id":"william-optics-adjustable-flat73a-for-z73","title":"William Optics Adjustable Flat73A for Z73","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eDesigned specifically for the William Optics ZenithStar 73 APO\u003c\/li\u003e\n\u003cli\u003eDelivers a 1.0x, perfectly flat field across full-frame sensors\u003c\/li\u003e\n\u003cli\u003eConnects to the Z73 focuser via a secure M63 thread\u003c\/li\u003e\n\u003cli\u003eProvides a standard M48 x 0.75 thread for camera T-rings and accessories\u003c\/li\u003e\n\u003cli\u003eAdjustable design ensures precise back focus for a wide range of cameras\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eWilliam Optics Adjustable Flat73A for Z73\u003c\/h2\u003e\n\u003cp\u003eThe William Optics Adjustable Flat73A is the essential imaging accessory for the ZenithStar 73 telescope, engineered to eliminate field curvature across sensors up to full-frame size. This 1.0x \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003eflattener\u003c\/a\u003e preserves the Z73's native focal length and f-ratio, connecting securely via its M63 thread and providing a standard M48 output for your camera. The 2-element optical design ensures that stars remain pinpoint sharp from the center of your image to the extreme corners.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFull-Frame Correction at 1.0x Power\u003c\/h3\u003e\n\u003cp\u003eThe Flat73A uses a 2-element optical design in two groups to correct the field curvature inherent in the Z73's fast, wide-field optics. As a 1.0x flattener, it does not act as a reducer or extender, so your telescope's focal length and focal ratio remain unchanged. This design is optimized to illuminate and correct for sensors up to a full-frame format, making it ideal for DSLRs, mirrorless cameras, and large-chip dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eZ73-Specific M63 Thread and M48 Camera Connection\u003c\/h3\u003e\n\u003cp\u003eDesigned for seamless integration, the Flat73A attaches directly to the ZenithStar 73's \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e drawtube using a robust M63 x 1 thread, ensuring a rigid, tilt-free connection. The camera side features the astrophotography standard M48 x 0.75 male thread, allowing you to connect a wide array of cameras from Canon, Nikon, Sony, Fuji, and more using a standard M48 \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e. The adjustable nature of the flattener is critical for achieving the precise sensor-to-flattener distance required for a perfectly flat field with different camera models.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"1.0x power\" mean for the William Optics Flat73A?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA \u003cstrong\u003e1.0x flattener\u003c\/strong\u003e corrects for field curvature without changing the focal length or f-ratio of your telescope. With the Flat73A, your ZenithStar 73 will operate at its native focal length, producing images with the same scale and field of view as it would without the flattener, but with the benefit of sharp stars across the entire frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Flat73A flattener with a telescope other than the Z73?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, the Flat73A is optically and mechanically designed specifically for the William Optics ZenithStar 73. It uses an M63 x 1 thread to attach to the Z73's focuser and its optical prescription is matched to that telescope's specific objective lens.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the maximum sensor size the Flat73A can illuminate and correct?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe William Optics Flat73A is designed to provide a corrected, unvignetted image circle for camera sensors up to \u003cstrong\u003efull-frame\u003c\/strong\u003e size. It is also perfectly suitable for smaller APS-C and Micro Four Thirds sensors.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect my Nikon Z mirrorless camera to the Flat73A?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou will need an M48 T-ring specifically made for the Nikon Z-mount. The Flat73A provides the standard \u003cstrong\u003eM48 x 0.75 male thread\u003c\/strong\u003e that the T-ring will attach to. The adjustable mechanism on the flattener then allows you to set the correct distance to your camera's sensor for optimal correction.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Flat73A improve my images of the North American Nebula (NGC 7000) with a Z73?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe ZenithStar 73 provides a wide field of view perfect for large targets like the North American Nebula (NGC 7000). However, without correction, stars at the edges of such a large object will appear elongated or out of focus. The Flat73A corrects this distortion, ensuring that every star across the vast nebula complex is rendered as a sharp, round point, resulting in a much cleaner and more professional final image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Flat73A necessary if I'm only using an APS-C camera with my Z73?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, absolutely. While an APS-C sensor is smaller than full-frame, the field curvature of the Z73 is still significant enough to be visible on an APS-C chip. Using the Flat73A will provide a noticeably flatter field, which is critical for accurate guiding, clean image stacking, and producing high-quality images where the corner performance matches the center.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eFlattener Power\u003c\/td\u003e\n\u003ctd\u003e1.0 x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e2 elements in 2 groups\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSupported Camera Formats\u003c\/td\u003e\n\u003ctd\u003eFull Frame, APS-C, M4\/3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Connection\u003c\/td\u003e\n\u003ctd\u003eM63 x 1 x 6 mm thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection\u003c\/td\u003e\n\u003ctd\u003eM48 x 0.75 x 4 mm thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSupported T-Mounts\u003c\/td\u003e\n\u003ctd\u003eCanon EF, RF, Nikon F, Z, Sony E, Pentax K, MFT (M4\/3), FUJI X\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Optical Length\u003c\/td\u003e\n\u003ctd\u003e65.5 mm (Flattener 39.5 mm + Rotator\/Adapter 26 mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e328.8 g \/ 0.72 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired back focus\u003c\/td\u003e\n\u003ctd\u003e66.2 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e43 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eWilliam Optics ZenithStar 73\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e1x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eWilliam Optics Adjustable Flat73A for Z73\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967221657885,"sku":"WO-P-FLAT73A","price":365.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/WO-P-FLAT73A-1.jpg?v=1722098931"},{"product_id":"william-optics-adjustable-reducer-flattener-flat73r-for-z73","title":"William Optics Adjustable Reducer Flattener Flat73R for Z73","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal length by a factor of 0.8x\u003c\/li\u003e\n\u003cli\u003eDesigned for the William Optics Zenithstar 73 telescope\u003c\/li\u003e\n\u003cli\u003eProvides edge-to-edge flat field for full-frame sensors\u003c\/li\u003e\n\u003cli\u003eConnects via a secure M63 x 1 thread\u003c\/li\u003e\n\u003cli\u003eFeatures a standard M48 x 0.75 camera thread\u003c\/li\u003e\n\u003cli\u003eIntegrated camera rotator for easy framing\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eWilliam Optics Adjustable Reducer Flattener Flat73R for Z73\u003c\/h2\u003e\n\u003cp\u003eThe William Optics Adjustable \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003eReducer Flattener\u003c\/a\u003e Flat73R is engineered specifically to transform the Zenithstar 73 \u003ca href=\"\/en-int\/collections\/apochromatic-refractors\"\u003eAPO refractor\u003c\/a\u003e into a wide-field \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e. Its 3-element, 3-group optical design delivers a 0.8x focal reduction, correcting for field curvature across full-frame sensors. The unit attaches via a robust M63 x 1 thread and presents a standard M48 x 0.75 T-mount to your camera, all while weighing just 573.9 g.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e0.8x Focal Reduction: A Wider, Faster Field for the Z73\u003c\/h3\u003e\n\u003cp\u003eThe core function of the Flat73R is its 0.8x reduction factor, which shortens the Z73's focal length for a significantly wider true field of view. This allows you to capture large targets like the Andromeda Galaxy (M31) or the entire Veil Nebula complex in a single frame. This reduction also concentrates incoming light, drastically shortening required exposure times and increasing your signal-to-noise ratio on faint deep-sky objects.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e3-Element, 3-Group Optics:\u003c\/strong\u003e This sophisticated design ensures high-contrast, sharp stars across the entire image circle, correcting for aberrations introduced by the reduction.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFull-Frame Illumination:\u003c\/strong\u003e The optics are designed to fully illuminate and flatten the field for sensors up to full-frame (36x24mm) format, preventing vignetting and distorted stars in the corners of your images.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eEngineered for the Z73: M63 Threads and an 89mm Optical Length\u003c\/h3\u003e\n\u003cp\u003eThe Flat73R provides a mechanically rigid connection to the Zenithstar 73. It threads directly onto the \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e's M63 x 1 thread, eliminating any potential for sag or flexure that can occur with compression fittings, especially with the added weight of a \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheel\u003c\/a\u003e and camera. The total optical length is 89 mm, composed of the 49 mm flattener body and a 40 mm \u003ca href=\"\/en-int\/collections\/rotators-and-tilt-adjusters\"\u003erotator\u003c\/a\u003e and adapter assembly that allows for precise framing of your target without loosening the camera.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSecure M63 Connection:\u003c\/strong\u003e Ensures perfect optical alignment and stability throughout an imaging session.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard M48 x 0.75 Camera Thread:\u003c\/strong\u003e Provides a wide, non-vignetting connection compatible with modern DSLR\/mirrorless \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-rings\u003c\/a\u003e and dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntegrated Rotator:\u003c\/strong\u003e The 40 mm adapter section includes a camera rotator, an essential feature for composing your shot without having to unthread your imaging train.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eZ73 Native vs. Reduced: What 0.8x Means for Your Images\u003c\/h3\u003e\n\u003cp\u003eWithout a corrector, the Z73 is a superb visual instrument, but for imaging, field curvature will soften stars at the edge of the frame. The Flat73R not only corrects this but fundamentally changes the telescope's imaging characteristics.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWider Field of View:\u003c\/strong\u003e The 0.8x reduction allows you to fit larger celestial objects into your frame compared to imaging at the native focal length. This is critical for large nebulae and nearby galaxies.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFaster Imaging:\u003c\/strong\u003e By reducing the focal ratio, the Flat73R gathers the same amount of light in a shorter time. An object that requires a 10-minute exposure at the native focal length can be captured with similar signal in just over 6 minutes, allowing you to gather more data in a single night.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTrade-off:\u003c\/strong\u003e The primary trade-off is a slight reduction in image scale. For smaller targets like most galaxies or planetary nebulae, imaging at the native focal length (with a flattener-only accessory) will yield a larger, more detailed image.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the William Optics Flat73R do for my Z73 telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Flat73R is a dual-purpose optical accessory. It acts as a \u003cstrong\u003efield flattener\u003c\/strong\u003e to correct the natural curvature of the focal plane, ensuring sharp, point-like stars across your entire sensor, especially large full-frame chips. It also acts as a \u003cstrong\u003e0.8x focal reducer\u003c\/strong\u003e, which widens your field of view and makes the telescope \"faster,\" reducing your exposure times.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Flat73R compatible with my full-frame camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The William Optics Flat73R is designed to provide excellent correction and illumination for camera sensors up to and including the \u003cstrong\u003efull-frame (36x24mm)\u003c\/strong\u003e format. It provides a standard M48 x 0.75 thread for connection, which is ideal for minimizing vignetting with large sensors.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I attach my camera to the Flat73R reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou attach your camera via the Flat73R's \u003cstrong\u003eM48 x 0.75 T-mount thread\u003c\/strong\u003e. You will need an M48 T-ring specific to your camera's mount (e.g., Canon EF, Nikon F, Sony E). This provides a secure, threaded connection for your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Flat73R's weight of 573.9 g affect my Z73's balance?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, adding the \u003cstrong\u003e573.9 g (1.27 lbs)\u003c\/strong\u003e of the reducer, plus your camera and any other accessories, will require you to rebalance your telescope on the mount. The Z73's focuser is robust enough to handle the load, but proper balance in both RA and Dec is critical for accurate tracking.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I frame the entire North American Nebula (NGC 7000) with the Z73 and Flat73R?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The wide field of view provided by the 0.8x reduction is ideal for very large targets like the North American Nebula (NGC 7000) and the nearby Pelican Nebula (IC 5070). With most APS-C and full-frame cameras, you should be able to capture the entire nebula complex in a single frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy would I use the Z73 without the Flat73R reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile the Flat73R is essential for wide-field imaging, you would remove it for visual observation with an \u003ca href=\"\/en-int\/collections\/eyepieces\"\u003eeyepiece\u003c\/a\u003e. For imaging smaller targets like the Whirlpool Galaxy (M51) or the Ring Nebula (M57), you might prefer to use a 1.0x flattener (sold separately) to maintain the telescope's native focal length for a larger image scale and more detail on the object.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReducer Power\u003c\/td\u003e\n\u003ctd\u003e0.8x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e3 Elements in 3 Groups\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003eFlattener 49 mm + Rotator\/Adapter 40 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Connection\u003c\/td\u003e\n\u003ctd\u003eM63 x 1 (7 mm length)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection\u003c\/td\u003e\n\u003ctd\u003eM48 x 0.75 (4 mm length)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSensor Coverage\u003c\/td\u003e\n\u003ctd\u003eFull Frame, APS-C, M4\/3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Mount Support\u003c\/td\u003e\n\u003ctd\u003eCanon EF, RF, Nikon F, Z, Sony E, Pentax K, MFT (M4\/3), FUJI X\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e573.9 g \/ 1.27 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired back focus\u003c\/td\u003e\n\u003ctd\u003e56.8 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eWilliam Optics ZenithStar 73\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e0.8x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eWilliam Optics Adjustable Reducer Flattener Flat73R for Z73\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967221788957,"sku":"WO-P-FLAT73R","price":389.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/William-Optics-Adjustable-Reducer-Flattener-Flat73R-for-Z73-P-FLAT73R-1__40133.1596133243.1280.1280.jpg?v=1684339331"},{"product_id":"william-optics-x0-8-reducer-flattener-7a","title":"William Optics x0.8 Reducer Flattener 7A","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal ratio by a factor of 0.8x\u003c\/li\u003e\n\u003cli\u003eTriplet lens design with 3 elements in 3 groups\u003c\/li\u003e\n\u003cli\u003eCorrects field curvature for full-frame sensors\u003c\/li\u003e\n\u003cli\u003eDesigned for specific William Optics refractors, including the FLT132, FLT156, GT102 and GT153\u003c\/li\u003e\n\u003cli\u003eStandard M48 x 0.75 camera connection thread\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eWilliam Optics x0.8 Reducer Flattener 7A\u003c\/h2\u003e\n\u003cp\u003eThe William Optics x0.8 \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003eReducer Flattener\u003c\/a\u003e 7A is an essential optical corrector engineered to convert select William Optics \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e into fast, wide-field \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrographs\u003c\/a\u003e. This unit reduces your telescope's focal length by a factor of 0.8x while its 3-element, 3-group triplet lens design delivers a perfectly flat field for full-frame camera sensors. It attaches via a robust M92 x 1 thread and has an optical length of 59.5 mm, with a back focus that depends on the telescope (69.24 mm on the FLT132).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eTriplet APO Optics: 0.8x Reduction for Full-Frame Sensors\u003c\/h3\u003e\n\u003cp\u003eThis corrector uses a three-element apochromatic lens structure to achieve its optical goals without introducing chromatic aberration. The 0.8x reduction factor effectively shortens your telescope's focal length, which provides a wider true field of view and reduces exposure times by nearly 40%. The flattener component corrects for the field curvature inherent in refractor optics, ensuring that stars in the corners of your full-frame or APS-C sensor are as sharp as those in the center.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eM92 Connection: Dedicated Fit for Specific William Optics Refractors\u003c\/h3\u003e\n\u003cp\u003eThe Flattener 7A is not a universal accessory; it is optically matched to specific William Optics telescopes to ensure optimal correction. It connects directly to the \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e drawtube using a secure M92 x 1 male thread. Back focus settings are available for the Gran Turismo 102 (must have a 3\" focuser), Gran Turismo 153, \u003ca href=\"\/en-int\/products\/william-optics-fluorostar-132\"\u003eFluorostar 132\u003c\/a\u003e, \u003ca href=\"\/en-int\/products\/william-optics-fluorostar-156\"\u003eFluorostar 156\u003c\/a\u003e, \u003ca href=\"\/en-int\/products\/william-optics-fluorostar-120\"\u003eFluorostar 120\u003c\/a\u003e (with back adapter) and Zenithstar 126. This dedicated design guarantees that the flattener's corrective power is perfectly aligned with the optical characteristics of these premium refractors.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCamera Interface:\u003c\/strong\u003e The camera side features a standard M48 x 0.75 thread, providing a wide, unvignetted connection for \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e, \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e, and full-frame camera \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-rings\u003c\/a\u003e.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBack Focus:\u003c\/strong\u003e The back focus depends on the telescope: 69.24 mm on the FLT132 and 65.3 mm on the FLT156, set with the adjustable back adapter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e At 888.4 g (1.96 lbs), it is a substantial optical element that requires a robust focuser to maintain collimation and prevent sag.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the William Optics Flattener 7A work with my telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis flattener is designed for a specific set of telescopes and will not work correctly with others. It is made for the GT102 (with 3\" focuser), GT153, FLT132, FLT156, FLT120 (with back adapter) and Zenithstar 126. It connects via an M92 x 1 thread.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the required back focus for the Flattener 7A?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe required back focus depends on the telescope: 69.24 mm for the FLT132 and 65.3 mm for the FLT156. Set it with the flattener's adjustable back adapter, then fine-tune with test shots.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 0.8x reduction affect my FLT132's imaging speed?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe FLT132 has a native focal ratio of f\/7.0. With the 0.8x reducer, the effective focal ratio becomes approximately f\/5.6. This \"faster\" system gathers light more quickly, allowing you to capture the same amount of signal on a target like the Heart Nebula (IC 1805) in significantly shorter exposure times.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use my full-frame camera with the William Optics Flattener 7A?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the Flattener 7A is designed to fully illuminate and correct for full-frame sensors (24x36mm format). It also works perfectly with smaller APS-C and M4\/3 sensors. The camera connects via a standard M48 x 0.75 T-ring.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Flattener 7A suitable for imaging the Andromeda Galaxy (M31) with a GT153?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. The GT153 is a long focal length instrument. The 0.8x reduction provided by the Flattener 7A creates a wider field of view, making it much easier to frame large targets like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000) in their entirety.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the \"3 Groups 3 Elements\" lens type mean for the Flattener 7A?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis refers to its optical design, which is a \u003cstrong\u003eTriplet\u003c\/strong\u003e. It uses three individual lens elements arranged in three groups. This sophisticated design allows it to reduce the focal length and flatten the field while maintaining excellent color correction (apochromatic performance), preventing bloated or blue-fringed stars.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eFlattener Power\u003c\/td\u003e\n\u003ctd\u003e0.8x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLens Design\u003c\/td\u003e\n\u003ctd\u003e3 Elements in 3 Groups (Triplet)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSupported Camera Formats\u003c\/td\u003e\n\u003ctd\u003eFull Frame, APS-C, M4\/3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Connection\u003c\/td\u003e\n\u003ctd\u003eM92 x 1 x 6.5 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection\u003c\/td\u003e\n\u003ctd\u003eM48 x 0.75 x 4 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003e59.5 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSupported T-Mounts\u003c\/td\u003e\n\u003ctd\u003eCanon EF, RF, Nikon F, Z, Sony E, Pentax K, MFT (M4\/3), FUJI X\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e888.4 g \/ 1.96 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired back focus\u003c\/td\u003e\n\u003ctd\u003e69.24 mm (FLT132), 65.3 mm (FLT156)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e44.4 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eFLT120 (with back adapter), FLT132, FLT156, GT102, GT153, ZS126\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e0.8x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eWilliam Optics x0.8 Reducer Flattener 7A\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967223623965,"sku":"WO-P-FLAT7A","price":1033.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/William-Optics-x0-8-Reducer-Flattener-7A-P-FLAT7A-1__75973.1596133243.1280.1280.jpg?v=1684339155"},{"product_id":"william-optics-wo-x0-72-reducer-flattener-8","title":"William Optics WO x0.72 Reducer Flattener 8","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal ratio by a factor of 0.72x\u003c\/li\u003e\n\u003cli\u003eCorrects field curvature for full-frame sensors\u003c\/li\u003e\n\u003cli\u003e3-element, 3-group optical design\u003c\/li\u003e\n\u003cli\u003eConnects to telescope via M92 x 1 thread\u003c\/li\u003e\n\u003cli\u003eStandard M48 x 0.75 camera-side threading\u003c\/li\u003e\n\u003cli\u003eWeighs 1098 g (2.42 lbs)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eWilliam Optics WO x0.72 Reducer Flattener 8\u003c\/h2\u003e\n\u003cp\u003eThe William Optics WO x0.72 Reducer Flattener 8 is engineered to transform high-focal-length William Optics \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e into faster, wide-field \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrographs\u003c\/a\u003e capable of illuminating full-frame sensors. Its 3-element, 3-group design provides a 0.72x focal reduction, significantly decreasing exposure times while correcting for field curvature from edge to edge. This unit connects to the telescope \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e via a robust M92 x 1 thread and provides a standard M48 x 0.75 thread for direct attachment to modern DSLR and dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA Faster, Wider Field: 0.72x Reduction for Large Refractors\u003c\/h3\u003e\n\u003cp\u003eThe primary function of the Flattener 8 is to reduce your telescope's effective focal length by a factor of 0.72x. For an f\/7 refractor, this transforms the optical system into a faster f\/5.04 instrument, cutting required exposure times by nearly 50%. This speed advantage allows you to capture more data on faint targets in a single night and increases the field of view to frame large objects like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eEdge-to-Edge Correction: Full-Frame Illumination with a 3-Element Design\u003c\/h3\u003e\n\u003cp\u003eDesigned specifically for large-aperture refractors, the Flattener 8 provides a corrected image circle that fully supports full-frame (36x24mm) camera sensors. The 3-element optical system in 3 groups is optimized to eliminate field curvature and minimize off-axis aberrations, ensuring that stars remain tight, pinpoint sources across the entire frame. This avoids the bloated, comatic stars in the corners that are common in uncorrected systems, delivering professional-grade astrophotography results.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eRobust Integration: M92 Telescope Thread and M48 Camera Support\u003c\/h3\u003e\n\u003cp\u003eThe Flattener 8 is built for a secure, flex-free imaging train. It attaches to compatible William Optics focusers using a large M92 x 1 male thread for a rigid connection. On the camera side, it terminates in a standard M48 x 0.75 male thread, the ideal interface for connecting \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e, \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e, and a wide range of camera-specific \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-rings\u003c\/a\u003e. At 1098 g (2.42 lbs), its solid construction ensures optical alignment is maintained, though it requires a robust focuser to handle the load.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich William Optics telescopes are compatible with the Flattener 8?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Flattener 8 is designed for William Optics' larger refractors that feature a focuser with a female M92 x 1 thread. It is made for the \u003ca href=\"\/en-int\/products\/william-optics-fluorostar-132\"\u003eFluorostar 132\u003c\/a\u003e (FLT132), \u003ca href=\"\/en-int\/products\/william-optics-fluorostar-156\"\u003eFluorostar 156\u003c\/a\u003e (FLT156), Gran Turismo 102 (GT102) and Gran Turismo 153 (GT153). Always confirm your telescope's focuser thread before purchasing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the WO Flattener 8 provide a fully corrected field for a full-frame sensor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it is explicitly designed to provide excellent correction and illumination for \u003cstrong\u003efull-frame sensors (36x24mm)\u003c\/strong\u003e, as well as smaller APS-C and M4\/3 formats. You can expect sharp, pinpoint stars from the center to the corners of your full-frame camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 0.72x reduction of the Flattener 8 affect my imaging time?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFocal reduction makes your telescope \"faster\" by concentrating the same amount of light onto a smaller area. A 0.72x reducer shortens exposure times by a factor of (0.72)^2, or approximately 0.52. This means a 10-minute exposure without the reducer would require only about 5 minutes to achieve the same signal-to-noise ratio with the Flattener 8 installed.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the required back focus for the William Optics Flattener 8?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile the optical length is 77 mm, the required back focus (the distance from the flattener's rear flange to the camera sensor) depends on the telescope: 63.4 mm for the FLT132, 60.8 mm for the FLT156, 67.1 mm for the GT102 and 60.4 mm for the GT153, with adjust distances of 8.4 mm, 5.8 mm, 12.1 mm and 5.4 mm respectively.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat are the connection threads on the WO Flattener 8?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Flattener 8 uses two primary threads:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTelescope Side:\u003c\/strong\u003e M92 x 1 male thread.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCamera Side:\u003c\/strong\u003e M48 x 0.75 male thread (also known as the 2\" filter thread standard).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 1098 g weight of the Flattener 8 a concern for my telescope's focuser?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAt 2.42 lbs, the Flattener 8 is a substantial piece of optical equipment. It requires a high-quality, robust focuser capable of handling heavy imaging trains without slipping or flexing. The rack-and-pinion focusers found on the William Optics telescopes it's designed for are more than capable of supporting this weight along with a camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReducer Power\u003c\/td\u003e\n\u003ctd\u003e0.72x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e3 Elements in 3 Groups\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Format Support\u003c\/td\u003e\n\u003ctd\u003eFull Frame, APS-C, M4\/3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Connection\u003c\/td\u003e\n\u003ctd\u003eM92 x 1 x 7.5 mm Thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection\u003c\/td\u003e\n\u003ctd\u003eM48 x 0.75 x 4 mm Thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSupported T-Mounts\u003c\/td\u003e\n\u003ctd\u003eCanon EF, RF; Nikon F, Z; Sony E; Pentax K; MFT (M4\/3); FUJI X\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003e77 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e1098 g \/ 2.42 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired back focus\u003c\/td\u003e\n\u003ctd\u003e63.4 mm (FLT132), 60.8 mm (FLT156), 67.1 mm (GT102), 60.4 mm (GT153)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e44.4 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eFLT132, FLT156, GT102, GT153\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e0.72x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eWilliam Optics WO x0.72 Reducer Flattener 8\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967224148253,"sku":"WO-P-FLAT8","price":1103.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/William-Optics-WO-x0-72-Reducer-Flattener-8-P-FLAT8-1__56697.1596133245.1280.1280.jpg?v=1684339346"},{"product_id":"baader-alan-gee-telecompressor-mark-ii","title":"Baader Alan Gee Telecompressor Mark II","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eDramatically widens the field of view of Schmidt-Cassegrain telescopes\u003c\/li\u003e\n\u003cli\u003eEngineered to produce a sharp, flat field for visual and photographic use\u003c\/li\u003e\n\u003cli\u003eCreates a significantly faster focal ratio for brighter images\u003c\/li\u003e\n\u003cli\u003eClose-couples with Baader\/Zeiss and Celestron binoviewers\u003c\/li\u003e\n\u003cli\u003eRequires precise spacing for optimal optical correction\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eBaader Alan Gee Telecompressor Mark II\u003c\/h2\u003e\n\u003cp\u003eThe Baader Alan Gee Telecompressor Mark II is a specialized optical corrector designed to solve the primary limitation of \u003ca href=\"\/en-int\/collections\/schmidt-cassegrain-telescopes\"\u003eSchmidt-Cassegrain telescopes\u003c\/a\u003e: their narrow, long-focus field of view. This telecompressor significantly reduces the effective focal length of your SCT, delivering a wider, flatter, and brighter image. It is a reconfigurable air-spaced doublet for visual use with 1.25in \u003ca href=\"\/en-int\/collections\/diagonals\"\u003estar diagonals\u003c\/a\u003e and \u003ca href=\"\/en-int\/collections\/binoviewers\"\u003ebinoviewers\u003c\/a\u003e, and for photography with DSLR and CCD cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eWiden Your SCT's Field for Rich-Field Views\u003c\/h3\u003e\n\u003cp\u003eStandard SCTs excel at high-power planetary views but struggle to frame large objects like the Andromeda Galaxy (M31) or the Pleiades (M45). The Alan Gee Telecompressor Mark II corrects this by shortening the telescope's light cone, expanding your true field of view to encompass these expansive targets. The result is a sharp, flat field that turns your SCT into a capable rich-field instrument. It fits 8\" and larger Schmidt-Cassegrains (35 mm free aperture); the Celestron C5 and C6 are not compatible because of their 27 mm baffle.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eOptimized for Baader, Zeiss, and Celestron Binoviewers\u003c\/h3\u003e\n\u003cp\u003eUnlike generic \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003efocal reducers\u003c\/a\u003e, the Alan Gee Mark II works with the long optical paths of star diagonals and binoviewers. Its design requires critical \"close coupling\" — a very specific and short distance between the compressor and the binoviewer prisms. This precise spacing is essential to achieve a fully illuminated and corrected field, limiting its use to specific Baader, Zeiss, and Celestron binoviewer models that can physically achieve this connection.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAlan Gee Mark II vs. Standard f\/6.3 Reducers\u003c\/h3\u003e\n\u003cp\u003eWhile a standard f\/6.3 reducer\/corrector offers a moderate increase in field of view, the Alan Gee Telecompressor is a more aggressive and specialized design. It provides a greater degree of focal reduction, but this comes with a critical trade-off.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard f\/6.3 Reducer:\u003c\/strong\u003e Offers more forgiving back-focus, making it compatible with a wide range of cameras and accessories. It's a general-purpose solution for both imaging and visual use.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBaader Alan Gee Mark II:\u003c\/strong\u003e Provides a wider, flatter, faster field for visual use with star diagonals and binoviewers and for photography with DSLR and CCD cameras up to APS-C size. It works best at its ideal 121 mm distance to the sensor or field stop, set with its spacer tubes.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy won't the Baader Alan Gee Mark II work with my Denkmeier or Tele Vue binoviewer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Alan Gee Mark II's optical design requires extremely close spacing to the binoviewer's prisms to function correctly. Most binoviewers have a long optical path (e.g., through a power-switch diagonal) that makes this physically impossible. It is specifically designed for direct, close-coupled attachment to certain Baader, Zeiss, and Celestron models.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Alan Gee Mark II for astrophotography?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. Baader supplies it for photographic use on Schmidt-Cassegrains with DSLR and CCD cameras. It is recommended for sensors up to APS-C (its fully illuminated image circle is 18 mm; remaining vignetting is easily removed in processing, full-frame shows more) and works best at 121 mm from its rear lens to the sensor, so \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e and \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e must be fitted into that distance. It cannot be used for photography on EdgeHD telescopes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Alan Gee Mark II affect the image brightness in my Celestron 11\" SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eBy reducing the telescope's effective focal ratio, the telecompressor concentrates the same amount of light into a smaller area. This creates a brighter image surface, which is especially beneficial for observing faint, extended objects like the Veil Nebula (NGC 6960). The background sky will appear brighter, but the nebula's contrast against it will increase.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the \"close coupling\" mentioned for the Alan Gee Mark II?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\"Close coupling\" means mounting the telecompressor lens directly in front of the binoviewer, which is the only way to reach focus with a binoviewer on an SCT. The ideal working distance is 121 mm between the rear lens and the focal plane; a longer distance gives a faster f-ratio (about f\/3.5 at 193 mm) but a smaller field of view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need to modify my SCT to use the Baader Alan Gee Mark II?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo permanent modification is needed, but you will need the correct adapters to thread the telecompressor directly to your binoviewer and then attach the entire assembly to your telescope's \u003ca href=\"\/en-int\/collections\/visual-adapters\"\u003evisual back\u003c\/a\u003e. For binoviewing it sits directly in front of the binoviewer, behind the star diagonal or T-2 prism; for photography or a 1.25in diagonal it is inserted into the telescope's baffle tube.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this telecompressor help me fit the entire Orion Nebula (M42) in the view of my 8\" SCT with a binoviewer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, this is precisely the kind of application the Alan Gee Mark II is designed for. A standard 8\" SCT with a binoviewer often cannot frame the full extent of M42's nebulosity. This telecompressor widens the field sufficiently to capture the entire object, from the Trapezium core to the fainter outer loops, in a single immersive view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet weight (kg)\u003c\/td\u003e\n\u003ctd\u003e0.09\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAR-Coating\u003c\/td\u003e\n\u003ctd\u003eMulti-Coated (MC)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eField Flattener, Telecompressor\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible telescopes\u003c\/td\u003e\n\u003ctd\u003eSchmidt-Cassegrain 8\" and larger (not C5\/C6)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical length (mm)\u003c\/td\u003e\n\u003ctd\u003e\u0026lt; 50\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired back focus\u003c\/td\u003e\n\u003ctd\u003e121 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e18 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear aperture\u003c\/td\u003e\n\u003ctd\u003e35 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eElements\u003c\/td\u003e\n\u003ctd\u003eAir-spaced doublet, multi-coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e0.59x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eLens cell with air-spaced doublet\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e2 spacer tubes (19 mm each)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eFlanged end ring\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSpacer ring (Teflon)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Baader_Planetarium_Alan_Gee_II_Telecompressor_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eBaader Planetarium Alan Gee II Telecompressor Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/baader-planetarium-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eBaader Planetarium Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Baader Planetarium","offers":[{"title":"Default Title","offer_id":44967374094621,"sku":"BAA-2454400","price":401.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-Alan-Gee-Telecompressor-Mark-II-1__02804.1597111079.1280.1280.jpg?v=1684341616"},{"product_id":"baader-m68-field-flattener","title":"Baader M68 Field Flattener","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eCorrects field curvature for astrophotography\u003c\/li\u003e\n\u003cli\u003eDesigned for Baader APO 95\/560 Travel Companion\u003c\/li\u003e\n\n\u003cli\u003eFeatures large M68 threads for a secure, wide-aperture connection\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section-center\"\u003e\n      \u003ch2\u003eBaader M68 Field Flattener\u003c\/h2\u003e\n      \u003cp\u003eThe Baader M68 Field Flattener is a dedicated optical corrector engineered to eliminate field curvature in specific high-end \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e. It is a 3-lens corrector matched to the Baader APO 95\/560 CaF2 Travel Companion, with 76.11 mm back focus and a 52 mm corrected field. By using a robust M68 thread, this flattener ensures a rigid, wide-aperture imaging train capable of illuminating large format sensors without vignetting.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eM68 Connection for Flat-Field Imaging\u003c\/h3\u003e\n      \u003cp\u003eThis corrector utilizes the Baader M68 system, a large-diameter thread standard chosen to provide a rigid connection and an unobstructed light path for modern imaging sensors. Unlike smaller M42 or M48 threads that can introduce vignetting with full-frame and larger chips, the M68 connection maintains the full illumination of the optical system. This ensures that stars remain pinpoint across the entire frame, from the center to the corners, without compromising brightness at the edges.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n    \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eDesigned for the Baader APO 95\/560 CaF2 Travel Companion\u003c\/h3\u003e\n      \u003cp\u003eThis is not a generic flattener; it is a specialized corrector calculated specifically for the Baader APO 95\/560 CaF2 Travel Companion. Field flatteners must be matched to the focal length and optical design of a telescope to work correctly. This unit provides the precise correction required by this \u003ca href=\"\/en-int\/collections\/apochromatic-refractors\"\u003eapochromat\u003c\/a\u003e, ensuring that their exceptional native image sharpness is delivered across the entire photographic field.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the purpose of the Baader M68 Field Flattener?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Baader M68 Field Flattener is an optical accessory designed for astrophotography. It corrects for field curvature, a natural aberration in refracting telescopes that causes stars at the edge of the field of view to appear out of focus. By inserting this flattener into the optical path, you can achieve sharp, pinpoint stars across your entire camera sensor.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Baader M68 Field Flattener with any telescope?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eNo. This field flattener is specifically designed and optically matched for use with the Baader APO 95\/560 CaF2 Travel Companion. Using it with other telescopes will not provide the correct optical correction and will likely result in poor image quality.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhy does the Baader M68 Field Flattener use M68 threads?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe M68 thread provides a larger clear aperture than more common M48 or M42 threads. This is critical for preventing vignetting (dimming at the corners of the image) when using cameras with large, full-frame sensors. The larger thread also creates a more rigid and stable connection for heavy imaging trains.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Baader M68 Field Flattener suitable for visual observing?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eWhile you could technically place an \u003ca href=\"\/en-int\/collections\/eyepieces\"\u003eeyepiece\u003c\/a\u003e behind it, this accessory is designed purely for photographic use. Field flatteners are not necessary for visual observation, as the human eye is much more tolerant of field curvature than a camera sensor. Its primary function is to create a flat focal plane for imaging.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Baader M68 Field Flattener perform with a full-frame camera on the Baader APO 95\/560?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Baader M68 Field Flattener is engineered to provide excellent correction across large sensor formats when paired with the Baader APO 95\/560. The M68 connection is specifically intended to support full-frame sensors, ensuring the telescope's high-contrast, apochromatic performance is maintained to the corners of the frame for objects like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000).\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat adapters are needed to connect my camera to the Baader M68 Field Flattener?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe required adapters depend on your specific camera and the necessary back focus distance. Baader Planetarium offers a comprehensive system of M68 adapters and extension tubes to achieve the correct spacing for various DSLR, mirrorless, and dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e. The back focus is 76.11 mm, and the flattener has an M68 female thread on the camera side (M68 male on the telescope side), so select M68 adapters that reach that distance.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired back focus\u003c\/td\u003e\n\u003ctd\u003e76.11 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e52 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eM68x1 Male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-side connection\u003c\/td\u003e\n\u003ctd\u003eM68x1 Female\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eBaader APO 95\/560 CaF2 Travel Companion\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eElements\u003c\/td\u003e\n\u003ctd\u003e3 lenses\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e390 g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e1.0x (field flattener)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eBaader M68 Field Flattener\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/baader-planetarium-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eBaader Planetarium Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Baader Planetarium","offers":[{"title":"Default Title","offer_id":44967374160157,"sku":"BAA-2458260","price":1056.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-M68-Field-Flattener-1__24858.1597111083.1280.1280.jpg?v=1684341642"},{"product_id":"lunt-8x-reducer-field-flattener","title":"Lunt .8X Reducer\/Field Flattener","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal length by a factor of 0.8x\u003c\/li\u003e\n\u003cli\u003eWidens the photographic field of view\u003c\/li\u003e\n\u003cli\u003eFlattens the image field for sharp, edge-to-edge stars\u003c\/li\u003e\n\u003cli\u003eDesigned for nighttime imaging with the Lunt MT80, MT100 \u0026amp; MT130\u003c\/li\u003e\n\u003cli\u003eMulti-coated optics for high contrast\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eLunt .8X Reducer\/Field Flattener\u003c\/h2\u003e\n\u003cp\u003eThe Lunt .8X Reducer\/Field Flattener is an essential astrophotography accessory that reduces your telescope's focal length by a factor of 0.8x, delivering a wider, flatter field of view for nighttime astrophotography with the Lunt MT80, MT100 and MT130.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 0.8x Focal Reduction for Wider Fields\u003c\/h3\u003e\n\u003cp\u003eThis accessory decreases your telescope's effective focal length by a factor of 0.8x, expanding your camera sensor's field of view. This is critical for imagers who need to capture wide night-sky fields without resorting to mosaics. The integrated flattener ensures the entire frame, from center to edge, remains sharp and free of distortion, a crucial feature for producing high-quality images.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMulti-Coated Optics:\u003c\/strong\u003e Minimizes internal reflections for high-contrast images.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDurable Construction:\u003c\/strong\u003e Housed in a lightweight yet sturdy aluminum body, it adds minimal weight to your imaging train, preserving your mount's balance and tracking accuracy.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eThe 0.8x Advantage in Imaging\u003c\/h3\u003e\n\u003cp\u003eBy reducing the focal length, this accessory also \"speeds up\" your optical system, lowering its effective f-ratio. A faster system allows shorter exposure times for the same image brightness.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the Lunt .8X Reducer\/Field Flattener primarily do?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Lunt .8X Reducer\/Field Flattener serves two main purposes for astrophotography. It \u003cstrong\u003ereduces your telescope's focal length by 0.8x\u003c\/strong\u003e to provide a wider field of view, and it \u003cstrong\u003eflattens the image field\u003c\/strong\u003e to ensure stars remain sharp across the entire sensor, from corner to corner.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Lunt .8X Reducer affect the f-ratio of an f\/10 telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt makes the telescope \"faster\" by reducing the f-ratio. To calculate the new f-ratio, you simply multiply the original f-ratio by the reduction factor. For an f\/10 telescope, the new photographic f-ratio would be \u003cstrong\u003ef\/8 (10 x 0.8)\u003c\/strong\u003e. This allows for shorter exposure times.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Lunt .8X Reducer recommended for visual observing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this accessory is designed specifically for astrophotography. While it may come to focus visually in some setups, its optical corrections are optimized for a flat sensor, not the human eye. For visual use, an \u003ca href=\"\/en-int\/collections\/eyepieces\"\u003eeyepiece\u003c\/a\u003e with a longer focal length is the correct way to achieve a wider true field of view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is a \"Field Flattener\" important for the Lunt .8X Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eMost telescopes naturally produce a curved focal plane, which means that if the center of your image is in focus, the edges will be slightly out of focus, causing stars to appear elongated. A field flattener corrects this curvature, ensuring the entire image projected onto your camera's flat sensor is perfectly sharp, a non-negotiable feature for serious astrophotography.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Lunt .8X Reducer work with my DSLR or a dedicated astronomy camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the Lunt .8X Reducer is designed to be compatible with a wide range of cameras, including DSLRs, mirrorless cameras, and dedicated CMOS\/CCD \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e. You will need the appropriate \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e and adapters to achieve the correct spacing for your specific camera model.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eSKU\u003c\/td\u003e\n\u003ctd\u003eLS130-.8CAAFF\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eKind\u003c\/td\u003e\n\u003ctd\u003eReducer \/ field flattener\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification factor\u003c\/td\u003e\n\u003ctd\u003e0.8x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eLunt LS80MT, LS100MT, LS130MT\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eLunt .8X Reducer\/Field Flattener\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/lunt-solar-system-warranty\" rel=\"noopener\" target=\"_blank\"\u003eLunt Solar Systems 5-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Lunt Solar Systems","offers":[{"title":"Default Title","offer_id":44967532560669,"sku":"LSS-CAA-RF","price":629.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Lunt-0-8x-Reducer-Flattener-1__51988.1598296520.1280.1280.jpg?v=1684343573"},{"product_id":"apm-riccardi-reducer-m63","title":"APM Riccardi Reducer M63","description":"\u003c!-- more --\u003e\u003cp\u003e\u003ci\u003eOur new reducer, calculated and designed from Riccardi\u003c\/i\u003e\u003cb\u003e\u003cbr\u003e\u003c\/b\u003e\u003cbr\u003e\u003cspan\u003eMassimo Riccardi, famous optical designer from Italy, designed for APM-Telescopes a new 3 element 0.75 x Apo-Reducer\/Flattener Corrector for all TMB-APM-LZOS Apochromatic Telescopes. Tests show that it also works on Apos from other manufacturers as well. The reducer shortens the focal length by a quarter and corrects the image circle - thereby converting your telescope into a fast astrograph!\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cb\u003eAssembly\u003cbr\u003e\u003c\/b\u003e\u003cbr\u003e\u003cspan\u003eThe connection to your telescope and camera occurs over an M63 x 1 thread. For the correct adjustment of the reducer\/flatener we can offer you an adjustment flange. \u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cb\u003eBackfocus\u003cbr\u003e\u003cbr\u003e\u003c\/b\u003e\u003cspan\u003eUsually  the reducer is screwed onto the focuser. The reducer can also be installed inside the focuser barrel, if the free aperture is equal to or larger than 68 mm.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eThe right backfocus for your telescope you will find in the enclosed PDF chart (see below). The total optical path of reducer plus backfocus plus focus change is between about 160 mm and 180 mm. \u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eThe correction is made for chips up to the full-format and perfect for the best known Kodak KAF 8300 chip.\u003c\/span\u003e\u003c\/p\u003e\u003cp\u003eConnection to camera: M63 x 1 ID-Thread\u003cbr\u003eConnection to telescope: M63 x 1 OD-Thread\u003cbr\u003eCoating: Fully multicoated\u003cbr\u003eHousing material: Aluminium\u003cbr\u003eRecommended distance from focal plane to connecting thread: watch PDF\u003cbr\u003eFocal length reduction: 0.75 x\u003cbr\u003eLenses: 3 Lenses\u003cbr\u003eOptical length without collimation flange: 180.05 mm\u003cbr\u003eOptical length with collimation flange: 189.05 mm\u003cbr\u003eFully corrected field: 40 mm\u003cbr\u003eLength: 71.7 mm (with Dustcaps 75 mm)\u003cbr\u003eDiameter: 67 mm\u003cbr\u003eWeight: 17.5 oz (with Dustcaps 18.9 oz)\u003c\/p\u003e","brand":"APM","offers":[{"title":"Default Title","offer_id":44967663960349,"sku":"APM-RIRED-M63-small","price":694.0,"currency_code":"CAD","in_stock":false}]},{"product_id":"apm-riccardi-reducer-m82","title":"APM Riccardi Reducer M82","description":"\u003c!-- more --\u003eAPM Riccardi Reducer M82","brand":"APM","offers":[{"title":"Default Title","offer_id":44967664124189,"sku":"APM-RIRED-M82-large","price":830.0,"currency_code":"CAD","in_stock":false}]},{"product_id":"apm-riccardi-flattener-m82-m77-model-1","title":"APM Riccardi Flattener M82-M77-Model 1","description":"\u003c!-- more --\u003eAPM Riccardi Flattener M82-M77-Model 1","brand":"APM","offers":[{"title":"Default Title","offer_id":44967664451869,"sku":"APM-RIFLAT1","price":690.0,"currency_code":"CAD","in_stock":false}]},{"product_id":"apm-riccardi-flattener-m82-m77-model-2","title":"APM Riccardi Flattener M82-M77-Model 2","description":"\u003c!-- more --\u003eAPM Riccardi Flattener M82-M77-Model 2","brand":"APM","offers":[{"title":"Default Title","offer_id":44967664550173,"sku":"APM-RIFLAT2","price":690.0,"currency_code":"CAD","in_stock":false}]},{"product_id":"sky-watcher-esprit-120-0-77x-reducer-flattener","title":"Sky-Watcher Esprit 120 0.77x Reducer\/Flattener","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eConverts Esprit 120 to 647 mm f\/5.4\u003c\/li\u003e\n\u003cli\u003eProvides a 0.77x focal reduction factor\u003c\/li\u003e\n\u003cli\u003eDelivers a 34 mm fully illuminated and flattened image circle\u003c\/li\u003e\n\u003cli\u003eOffers dual back focus options of 95 mm and 55 mm\u003c\/li\u003e\n\u003cli\u003eFeatures a built-in 2\" filter cell and M48 adapter\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eSky-Watcher Esprit 120 0.77x Reducer\/Flattener\u003c\/h2\u003e\n\u003cp\u003eThe Sky-Watcher Esprit 120 0.77x Reducer\/Flattener is a dedicated 3-element corrector that transforms the Esprit 120 from its native 840 mm f\/7 optics into a faster 647 mm f\/5.4 \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e. This accessory provides a 34 mm flattened and illuminated field while offering two distinct back focus distances of 95 mm and 55 mm for versatile camera integration. Weighing just 910 g, it threads directly onto the Esprit 120's \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e drawtube.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFrom f\/7 to f\/5.4 with 0.77x Reduction\u003c\/h3\u003e\n\u003cp\u003eBy applying a 0.77x reduction factor, this accessory shortens the Esprit 120's focal length to 647 mm and increases its photographic speed to f\/5.4. The shorter focal length gives a wider field of view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 34mm Flattened Field for the Esprit 120\u003c\/h3\u003e\n\u003cp\u003eEngineered as both a reducer and a flattener, this 3-element optical accessory is designed specifically for the Esprit 120. It corrects for field curvature to ensure sharp, point-like stars across a 34 mm image circle. It is a full-frame reducer\/flattener with full illumination and minimized color fringing across the 34 mm imaging plane.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eDual 95mm\/55mm Back Focus and Filter Integration\u003c\/h3\u003e\n\u003cp\u003eThe reducer provides two standard back focus distances to accommodate different imaging setups. The native 95 mm back focus is measured from the M78 x 1 male thread; the supplied rings give 95 mm with any DSLR, and \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e need a custom ring. The back focus spacer and M48 ring also give 55 mm. For filtering, a 48 mm (2\") filter can be mounted inside the DSLR extender tube's closing ring, which has a 48 x 0.75 thread.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Esprit 120 0.77x Reducer on a telescope other than the Sky-Watcher Esprit 120?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. This is a dedicated optical accessory designed exclusively for the Sky-Watcher Esprit 120 (840 mm f\/7). It is not compatible with other telescopes, even \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e with similar apertures or focal lengths, as its corrective properties are matched precisely to the Esprit 120's optical design.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat sensor sizes will the Sky-Watcher Esprit 120 Reducer's 34mm image circle cover?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt gives full illumination and field flatness across a 34 mm imaging plane. Compare 34 mm with your sensor's \u003ca href=\"\/en-int\/collections\/diagonals\"\u003ediagonal\u003c\/a\u003e before buying.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I install 2\" filters with the Esprit 120 0.77x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA 48 mm (2\") filter can be mounted inside the DSLR extender tube: unscrew the closing ring at the rear, insert the filter without overtightening and refit the ring, which has a 48 x 0.75 thread inside.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat are the 95mm and 55mm back focus options for on the Esprit 120 Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e95 mm is the distance from the start of the M78 x 1 male thread to the sensor. The supplied rings give 95 mm with any DSLR; astronomy cameras need a custom ring with a female M78 x 1 thread. The 55 mm figure applies with the back focus spacer and M48 ring.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I attach a camera with M48 threads to the Esprit 120 0.77x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer includes an M48 adapter ring. This adapter threads onto the reducer's primary M78 x 1 exit thread, converting it to an M48 x 0.75 thread. This allows you to directly connect camera-specific M48 \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-rings\u003c\/a\u003e or other M48-threaded accessories.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Sky-Watcher 0.77x Reducer change the Esprit 120's focal length?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The 0.77x reduction factor changes the telescope's optical characteristics for imaging. It reduces the native 840 mm focal length to 647 mm and increases the focal ratio from f\/7 to a faster f\/5.4. This gives a wider field of view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eManufacturer SKU\u003c\/td\u003e\n\u003ctd\u003eS20209\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescope\u003c\/td\u003e\n\u003ctd\u003eSky-Watcher Esprit 120 (840 mm f\/7)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e3-element Reducer\/Flattener\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.77x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Length\u003c\/td\u003e\n\u003ctd\u003e647 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/5.4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIlluminated \u0026amp; Flattened Field\u003c\/td\u003e\n\u003ctd\u003e34 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNative Back Focus\u003c\/td\u003e\n\u003ctd\u003e95 mm from M78 x 1 male thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStandard Back Focus\u003c\/td\u003e\n\u003ctd\u003e55 mm with back focus spacer and M48 ring\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Connection\u003c\/td\u003e\n\u003ctd\u003eThreads directly onto Esprit 120 focuser drawtube\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eExit Thread\u003c\/td\u003e\n\u003ctd\u003eM78 x 1 male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Adapter Thread\u003c\/td\u003e\n\u003ctd\u003eM48 x 0.75 (with supplied adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Support\u003c\/td\u003e\n\u003ctd\u003eBuilt-in 2\" filter cell; 48 mm (2\") filter can also mount inside the DSLR extender tube (48 x 0.75 thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e910 g (2.0 lb) including end caps\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e0.77x reducer\/flattener\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eEnd caps (set)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eM48 adapter ring\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Sky-Watcher_Esprit_EDX_120_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/sky-watcher-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSky-Watcher 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Sky-Watcher","offers":[{"title":"Default Title","offer_id":44967731724573,"sku":"SW-S20209","price":730.0,"currency_code":"CAD","in_stock":true}]},{"product_id":"sky-watcher-esprit-150-0-77x-reducer-flattener","title":"Sky-Watcher Esprit 150 0.77x Reducer\/Flattener","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal ratio to f\/5.4\u003c\/li\u003e\n\u003cli\u003eProvides a 36mm fully illuminated field\u003c\/li\u003e\n\u003cli\u003e0.77x reduction factor changes focal length to 810mm\u003c\/li\u003e\n\u003cli\u003eCuts exposure times by 68%\u003c\/li\u003e\n\u003cli\u003eSupplies 55mm back focus with included M48 adapter and spacer\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eSky-Watcher Esprit 150 0.77x Reducer\/Flattener\u003c\/h2\u003e\n\u003cp\u003eThe Sky-Watcher Esprit 150 0.77x Reducer\/Flattener is a dedicated optical corrector that transforms the Esprit 150ED and 150EDX \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e from f\/7 to a much faster f\/5.4. This 0.77x reduction shortens the telescope's focal length from 1050mm to 810mm, cutting required exposure times by about 68%. It flattens the field for pinpoint stars to the edge and delivers a 36mm fully illuminated field suitable for full-frame sensors, with a 90mm back focus, or 55mm with the supplied M48 adapter and back focus spacer.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFrom f\/7 to f\/5.4: A 68% Reduction in Exposure Time\u003c\/h3\u003e\n\u003cp\u003eBy converting the Esprit 150's native f\/7 optical system to f\/5.4, this reducer cuts the exposure time needed by about 68% compared with the native configuration. You can collect more data in a single night or capture faint detail in shorter sub-exposures.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 36mm Corrected Field for Full-Frame Sensors\u003c\/h3\u003e\n\u003cp\u003eThis corrector not only reduces focal length but also flattens the field for pinpoint stars to the edge. Its 36mm fully illuminated field is large enough for full-frame sensors.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e90mm and 55mm Back Focus Options\u003c\/h3\u003e\n\u003cp\u003eThe reducer has 90mm of back focus. By installing the supplied M48 adapter and back focus spacer, the required back focus becomes 55mm, making it straightforward to attach cameras and \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e with M48 threads.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e90mm Native Back Focus:\u003c\/strong\u003e Back focus of the reducer without the adapter and spacer.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e55mm Back Focus:\u003c\/strong\u003e Achieved with the included spacer and M48 adapter, for cameras and filter wheels with M48 threads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDedicated Design:\u003c\/strong\u003e This corrector is matched to the Esprit 150ED and 150EDX refractors. Esprit reducer flatteners are not compatible with other telescopes.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the correct back focus for my setup with the Esprit 150 Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer's back focus is \u003cstrong\u003e90mm\u003c\/strong\u003e. With the supplied M48 adapter and back focus spacer installed, the required back focus becomes \u003cstrong\u003e55mm\u003c\/strong\u003e, which makes it straightforward to attach cameras and filter wheels with M48 threads.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Esprit 150 0.77x Reducer compatible with my non-Sky-Watcher telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. This reducer\/flattener is a dedicated corrector for the Sky-Watcher Esprit 150ED and Esprit 150EDX refractors. Esprit reducer flatteners are specifically designed for their telescope and are not compatible with other telescopes, even refractors with the same aperture and focal length.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the 68% exposure time reduction mean for my Esprit 150EDX imaging sessions?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA 68% reduction means an exposure that would take 10 minutes at the native f\/7 takes about 3 minutes and 12 seconds at f\/5.4. This lets you gather about three times as much data in the same amount of time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Esprit 150 Reducer work with my full-frame camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer delivers a 36mm fully illuminated field, which retailers describe as large enough for full-frame sensors.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I achieve the 55mm back focus with the Esprit 150 Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer ships with a back focus spacer and an M48 thread adapter. With both installed, the required back focus becomes 55mm instead of the native 90mm.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eManufacturer SKU\u003c\/td\u003e\n\u003ctd\u003eS20215\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescopes\u003c\/td\u003e\n\u003ctd\u003eSky-Watcher Esprit 150ED \u0026amp; 150EDX (1050 mm f\/7)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.77x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Length\u003c\/td\u003e\n\u003ctd\u003e810 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/5.4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNative Focal Length \/ Ratio\u003c\/td\u003e\n\u003ctd\u003e1050 mm \/ f\/7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eExposure Time Reduction\u003c\/td\u003e\n\u003ctd\u003e68% (vs. f\/7)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFully Illuminated Field\u003c\/td\u003e\n\u003ctd\u003e36 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus (Native)\u003c\/td\u003e\n\u003ctd\u003e90 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus (with Adapter)\u003c\/td\u003e\n\u003ctd\u003e55 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection\u003c\/td\u003e\n\u003ctd\u003eM48 (with supplied adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e910 g (2.0 lb) including end caps\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e0.77x Reducer\/Flattener\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eMetal Thread-on Caps (set)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eBack Focus Spacer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eM48 Thread Adapter\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/sky-watcher-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSky-Watcher 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Sky-Watcher","offers":[{"title":"Default Title","offer_id":44967731757341,"sku":"SW-S20215","price":730.0,"currency_code":"CAD","in_stock":true}]},{"product_id":"sky-watcher-evoguide-50ed-flattener","title":"Sky-Watcher Evoguide 50ED Flattener","description":"\u003cul class=\"DAV-feature-list\"\u003e\n  \u003cli\u003eTransforms the Evoguide 50ED\/DX into a wide-field astrograph\u003c\/li\u003e\n  \u003cli\u003eProduces a 28mm corrected imaging circle for flat, sharp stars\u003c\/li\u003e\n  \u003cli\u003eStandard 17.5mm back focus simplifies camera and accessory spacing\u003c\/li\u003e\n  \u003cli\u003eOffers a massive 5.33° x 3.57° field of view with APS-C sensors\u003c\/li\u003e\n  \u003cli\u003eConnects securely via standard T-threads or a 1.25\" nosepiece\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n      \u003cdiv class=\"DAV-bg-light\"\u003e\n        \u003cdiv class=\"DAV-section-center\"\u003e\n          \u003ch2\u003eSky-Watcher Evoguide 50ED Flattener\u003c\/h2\u003e\n          \u003cp\u003eThe Sky-Watcher Evoguide 50ED Flattener unlocks the full astrophotography potential of the Evoguide 50ED and 50DX scopes, converting your high-end \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eguidescope\u003c\/a\u003e into a premium wide-field imaging instrument. This corrector produces a 28mm imaging circle, delivering pinpoint stars across the frame with cameras up to APS-C sensor size. With a generous 5.33° x 3.57° field of view on a crop-sensor camera and a standard 17.5mm back focus, it provides the optical correction needed to capture entire nebulae and star clusters in a single shot.\u003c\/p\u003e\n        \u003c\/div\u003e\n      \u003c\/div\u003e\n      \u003cdiv class=\"DAV-bg-light\"\u003e\n        \u003cdiv class=\"DAV-section\"\u003e\n          \u003ch3\u003e28mm Imaging Circle: Edge-to-Edge Star Correction\u003c\/h3\u003e\n          \u003cp\u003eThe primary function of this flattener is to eliminate the field curvature inherent in the Evoguide's fast optical system. It generates a 28mm corrected image circle, ensuring that stars in the corners of your frame are as sharp and round as those in the center. This level of correction is ideal for popular APS-C sized sensors, preventing elongated stars and allowing you to use the entire frame for your composition.\u003c\/p\u003e\n        \u003c\/div\u003e\n      \u003c\/div\u003e\n      \u003cdiv class=\"DAV-bg-light\"\u003e\n        \u003cdiv class=\"DAV-section\"\u003e\n          \u003ch3\u003e17.5mm Back Focus for Simplified Imaging Trains\u003c\/h3\u003e\n          \u003cp\u003eAchieving correct spacing is critical for any flattener, and this unit makes it simple with a 17.5mm back focus requirement. This distance is easily managed with standard T-thread extension rings and adapters for most modern CMOS and DSLR \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e. The fixed spacing removes the guesswork, letting you connect your camera and start imaging with confidence that your optics are correctly aligned for the flattest possible field.\u003c\/p\u003e\n          \u003cul\u003e\n            \u003cli\u003e\n\u003cstrong\u003eDirect T-Thread Connection:\u003c\/strong\u003e The flattener features a male T-thread for a secure, rigid connection to your \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheel\u003c\/a\u003e, off-axis guider, or camera's \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e adapter.\u003c\/li\u003e\n            \u003cli\u003e\n\u003cstrong\u003e1.25\" Accessory Mount:\u003c\/strong\u003e For smaller \u003ca href=\"\/en-int\/collections\/guide-cameras\"\u003eguide cameras\u003c\/a\u003e or planetary imagers, a 1.25\" opening provides a secondary connection method, adding flexibility to your setup.\u003c\/li\u003e\n          \u003c\/ul\u003e\n        \u003c\/div\u003e\n      \u003c\/div\u003e\n      \u003cdiv class=\"DAV-bg-light\"\u003e\n        \u003cdiv class=\"DAV-section\"\u003e\n          \u003ch3\u003eCapture Expansive Views: 5.33° x 3.57° on APS-C\u003c\/h3\u003e\n          \u003cp\u003eWhen paired with an APS-C camera, this flattener and the Evoguide 50ED create an imaging system with an immense 5.33° by 3.57° field of view. This is wide enough to frame the entirety of the Andromeda Galaxy (M31), the North American Nebula (NGC 7000), or the sprawling star-forming regions within the constellation Cygnus. It turns your guidescope into a dedicated, high-quality lens for capturing the largest deep-sky objects.\u003c\/p\u003e\n        \u003c\/div\u003e\n      \u003c\/div\u003e\n    \n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main purpose of the Evoguide 50ED Flattener?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eThe Evoguide 50ED Flattener corrects for field curvature in the Sky-Watcher Evoguide 50ED and 50DX telescopes. Without it, stars at the edge of an image will appear stretched or out of focus. This accessory ensures sharp, pinpoint stars across a \u003cstrong\u003e28mm imaging circle\u003c\/strong\u003e, making the guidescope suitable for high-quality, wide-field astrophotography.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I achieve the required 17.5mm back focus for my camera?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eThe \u003cstrong\u003e17.5mm back focus\u003c\/strong\u003e is the distance from the flattener's rear T-thread to your camera's sensor. Most dedicated astronomy cameras have a sensor-to-flange distance of around 12.5mm or 17.5mm. You may need a small T-thread spacer to achieve the exact distance. For DSLRs, the standard 44mm flange distance of a Canon EF-mount or 46.5mm of a Nikon F-mount means you will need a specific T-ring adapter designed for this back focus, which is typically shorter than the standard 55mm setup.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use a full-frame camera with the Evoguide 50ED Flattener?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eNo, this flattener is optimized for a \u003cstrong\u003e28mm imaging circle\u003c\/strong\u003e, which is best suited for sensors up to APS-C size. While a full-frame camera (which has a ~43mm diagonal) will physically connect, you will experience significant vignetting and distorted stars in the outer portions of the frame beyond the corrected circle.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of field of view can I expect with the Evoguide 50ED Flattener on the Heart Nebula (IC 1805)?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eUsing a camera with an APS-C sensor (like a ZWO ASI2600MC Pro or a Canon DSLR), the Evoguide 50ED with this flattener provides a field of view of \u003cstrong\u003e5.33° x 3.57°\u003c\/strong\u003e. This is an extremely wide field, perfect for capturing the entire Heart Nebula and its neighboring Soul Nebula (IC 1848) together in a single frame with room to spare.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect a guide camera like a ZWO ASI120MM Mini to the flattener?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eThe \u003ca href=\"\/en-int\/products\/zwo-asi120mm-mini-mono\"\u003eZWO ASI120MM Mini\u003c\/a\u003e has a 1.25\" form factor. You can insert it directly into the \u003cstrong\u003e1.25\" opening\u003c\/strong\u003e on the back of the flattener and secure it with the set screws. This allows you to use the Evoguide for both imaging and guiding simultaneously if you are using a separate, larger telescope as your main imaging scope.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eAre the dust caps on the Evoguide 50ED Flattener standard plastic caps?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eNo, the flattener comes with high-quality, threaded metal dust caps. These provide superior protection for the optics by screwing on securely, preventing them from falling off and ensuring a better seal against dust compared to standard push-fit plastic caps.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eSKU\u003c\/td\u003e\n          \u003ctd\u003eSW-S20214\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eUPC\u003c\/td\u003e\n          \u003ctd\u003e050234202145\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eCompatibility\u003c\/td\u003e\n          \u003ctd\u003eSky-Watcher Evoguide 50ED, Sky-Watcher Evoguide 50DX\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eCorrected Imaging Circle\u003c\/td\u003e\n          \u003ctd\u003e28mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eBack Focus\u003c\/td\u003e\n          \u003ctd\u003e17.5mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eCamera Connections\u003c\/td\u003e\n          \u003ctd\u003eT-thread (M42x0.75), 1.25\" nosepiece receptacle\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eField of View (with APS-C Sensor)\u003c\/td\u003e\n          \u003ctd\u003e5.33° x 3.57°\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eCaps\u003c\/td\u003e\n          \u003ctd\u003eThreaded metal front and rear caps\u003c\/td\u003e\n        \u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e1.0x (field flattener)\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n        \u003cimg class=\"DAV-img-box\" alt=\"Sky-Watcher Evoguide 50ED Flattener\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/SW-S20214_1.jpg?v=1684877797\"\u003e\n        \u003cdiv\u003e\n          \u003cp class=\"DAV-item-title\"\u003eEvoguide 50ED Flattener\u003c\/p\u003e\n          \u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n        \u003c\/div\u003e\n      \u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n        \u003cimg class=\"DAV-img-box\" alt=\"Threaded Metal Dust Caps\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/SW-S20214_3.jpg?v=1684877797\"\u003e\n        \u003cdiv\u003e\n          \u003cp class=\"DAV-item-title\"\u003eThreaded Metal Caps\u003c\/p\u003e\n          \u003cp class=\"DAV-item-subtitle\"\u003e× 2\u003c\/p\u003e\n        \u003c\/div\u003e\n      \u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/sky-watcher-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSky-Watcher 2-Year Limited Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Sky-Watcher","offers":[{"title":"Default Title","offer_id":44967731855645,"sku":"SW-S20214","price":160.0,"currency_code":"CAD","in_stock":true}]},{"product_id":"zwo-atmospheric-dispersion-corrector","title":"ZWO Atmospheric Dispersion Corrector","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eCorrects atmospheric dispersion for sharper planetary images\u003c\/li\u003e\n\u003cli\u003eUses two H-K9L prisms with 2° deviation angles\u003c\/li\u003e\n\u003cli\u003eFeatures 1\/10 wave optical accuracy to preserve resolution\u003c\/li\u003e\n\u003cli\u003e1.25” barrels, with a non-marring brass compression ring on the eyepiece holder\u003c\/li\u003e\n\u003cli\u003eIndependent levers and a rotatable scale for precise adjustment\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eZWO ADC Atmospheric Dispersion Corrector\u003c\/h2\u003e\n\u003cp\u003eThe ZWO ADC Atmospheric Dispersion Corrector neutralizes the color fringing caused by Earth's atmosphere, sharpening planetary and lunar views. It uses two counter-rotating H-K9L prisms, each with a 2° deviation angle and polished to a 1\/10 wave accuracy, to recombine the dispersed spectrum of light back into a single, focused point. This correction is critical for high-resolution imaging, especially when planets are at low altitudes where dispersion is most severe.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e1\/10 Wave Correction for High-Resolution Imaging\u003c\/h3\u003e\n\u003cp\u003eAtmospheric dispersion acts like a weak prism, smearing a planet's light into a vertical rainbow that blurs fine detail. The ZWO ADC introduces an equal and opposite dispersion, effectively canceling the atmospheric effect. With optical surfaces polished to a 1\/10 wave accuracy, the ADC corrects this color separation without introducing its own aberrations, preserving the native resolution of your telescope and letting you resolve finer cloud bands on Jupiter or subtler crater details on the Moon.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003ePrecise Adjustment with a Rotatable 360° Scale\u003c\/h3\u003e\n\u003cp\u003eProperly using an ADC requires aligning its null point with the horizon and then adjusting the prisms to match the level of dispersion. The ZWO ADC simplifies this process with an intuitive control system. The rotatable scale and white locking screw let you easily set the horizontal \"zero\" position without rotating the entire ADC in your \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e. From there, two independent levers allow you to dial in the precise amount of correction needed, which you can see in real-time on your camera's live view.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSynchronized Levers:\u003c\/strong\u003e Overlapping slots allow the two prism levers to be moved together, simplifying the initial adjustment process.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRotatable Scale:\u003c\/strong\u003e Lets you orient the measurement scale to the horizon, making it easy to set the levers symmetrically for optimal correction.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSecure Connections:\u003c\/strong\u003e The 1.25\" \u003ca href=\"\/en-int\/collections\/visual-adapters\"\u003eeyepiece holder\u003c\/a\u003e uses a brass compression ring, ensuring a firm grip on your camera or \u003ca href=\"\/en-int\/collections\/eyepieces\"\u003eeyepiece\u003c\/a\u003e without scratching its barrel.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eWhen to Use the ZWO ADC\u003c\/h3\u003e\n\u003cp\u003eAn ADC is not always necessary, but it is an essential tool for dedicated planetary imagers. Its effect is most dramatic when a target is below 60 degrees of altitude. For observers in the northern hemisphere imaging Jupiter or Saturn during their low-altitude apparitions, an ADC is the difference between a soft, color-fringed image and a sharp, detailed one.\u003c\/p\u003e\n\u003cp\u003eThe primary trade-off is a minor reduction in light throughput from the extra glass. For bright targets like the planets and the Moon, this is insignificant compared to the massive gain in sharpness. However, for faint deep-sky objects where every photon counts and dispersion is less noticeable, an ADC is typically removed from the imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the ZWO ADC improve planetary images?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhen light from a planet passes through Earth's atmosphere, it gets dispersed into a spectrum, causing a blue fringe on top and a red fringe on the bottom. This blurs the image. The \u003cstrong\u003eZWO ADC\u003c\/strong\u003e uses a pair of prisms to create an opposite dispersion effect, recombining the colors into a single sharp point and restoring fine detail.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the ZWO ADC necessary when planets are high in the sky?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhen a celestial object is directly overhead (near the zenith), atmospheric dispersion is minimal, and an ADC provides little to no benefit. Its function becomes critical when objects are below about 60° altitude. The lower the object, the more atmosphere its light travels through, and the more valuable the ADC becomes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I set up the ZWO ADC for imaging Jupiter from my backyard?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFirst, insert the ADC into your focuser and attach your camera. Point at Jupiter and achieve focus. Rotate the entire ADC until the adjustment levers are perfectly horizontal. Lock the rotatable scale so the \"0\" mark aligns with the levers. Then, slowly and symmetrically move the levers apart, watching your live view screen. You will see the red and blue color fringes merge and the image become noticeably sharper. Fine-tune for the best possible view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the ZWO ADC for visual observing with an eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. While most commonly used for imaging, the ZWO ADC works perfectly for visual observation. Simply place it between the \u003ca href=\"\/en-int\/collections\/diagonals\"\u003ediagonal\u003c\/a\u003e and your eyepiece. The improvement in sharpness and the reduction of color fringing on planets and the lunar limb will be immediately apparent, especially at high magnification.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the ZWO ADC useful for deep-sky objects like galaxies or nebulae?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eGenerally, no. Atmospheric dispersion primarily affects very bright, sharp point-sources of light like stars and planets. Faint, diffuse deep-sky objects are not resolved with enough detail for dispersion to be a significant problem. The slight light loss from the ADC's prisms would be more detrimental than any minor sharpening benefit.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the purpose of the 2° prism deviation angle on the ZWO ADC?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 2° deviation angle determines the maximum amount of corrective power the ADC can apply. A larger deviation angle can correct stronger dispersion, which matters most when a planet is low in the sky.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eSKU\u003c\/td\u003e\n\u003ctd\u003eZWO-ADC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrism Material\u003c\/td\u003e\n\u003ctd\u003eH-K9L (BK-7 Equivalent)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrism Angle\u003c\/td\u003e\n\u003ctd\u003e2°\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Surface Accuracy\u003c\/td\u003e\n\u003ctd\u003e1\/10λ\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConnections\u003c\/td\u003e\n\u003ctd\u003e1.25\" Barrel (Nosepiece \u0026amp; Holder)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClamping Mechanism\u003c\/td\u003e\n\u003ctd\u003eBrass Compression Ring\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" nosepiece (on M42x0.75 thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-side connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" holder (on M42x0.75 thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear aperture\u003c\/td\u003e\n\u003ctd\u003e22.6 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eLunar and planetary imaging\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eZWO Atmospheric Dispersion Corrector\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e1.25\" Dust Cap\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e1.25\" Dust Plug\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cameracompany.com\/downloads\/1418\/ADC%20Quick%20Start%20Guide.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Quick Start Guide\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.zwoastro.com\/software\/\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/zwo-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eZWO 2-Year Limited Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"ZWO","offers":[{"title":"Default Title","offer_id":44967733821725,"sku":"ZWO-ADC","price":188.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/ZWO-ADC-1__01697.1649100925.1280.1280.jpg?v=1684345669"},{"product_id":"sharpstar-61edph-0-8x-focal-reducer","title":"SharpStar 61EDPH 0.8x Focal Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eConverts the SharpStar 61EDPH to a fast f\/4.5 astrograph\u003c\/li\u003e\n\u003cli\u003eProvides a 44mm image circle for full-frame sensor coverage\u003c\/li\u003e\n\u003cli\u003eThree-element air-spaced optical design\u003c\/li\u003e\n\u003cli\u003eStandard 55mm back focus for easy camera integration\u003c\/li\u003e\n\u003cli\u003eWeighs only 0.45kg\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eSharpStar 61EDPH 0.8x Focal Reducer\u003c\/h2\u003e\n\u003cp\u003eThe SharpStar 61EDPH 0.8x Focal Reducer transforms its dedicated telescope into a fast f\/4.5 \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e, using a three-element air-spaced optical design to deliver a flat 44mm image circle. This reducer provides a standard 55mm back focus for easy camera integration and adds only 0.45kg to your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAn f\/4.5 System for the 61EDPH\u003c\/h3\u003e\n\u003cp\u003eDesigned exclusively for the SharpStar 61EDPH and 61EDPH II \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e, this 0.82x reducer shortens the telescope's focal ratio from f\/5.5 to a significantly faster f\/4.5. This conversion allows you to capture the same amount of light in approximately 67% of the time, dramatically increasing your efficiency during short imaging nights and enabling deeper exposures on faint deep-sky objects.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA Flat 44mm Image Circle for Full-Frame Sensors\u003c\/h3\u003e\n\u003cp\u003eThe reducer's three-element, air-spaced optics are engineered to produce a corrected 44mm image circle. This is large enough to illuminate full-frame sensors (24x36mm) without significant vignetting, ensuring your images have even brightness from corner to corner. With full-surface multi-layer coatings, the system maintains high contrast and minimizes internal reflections for clean, sharp stars across the entire field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eStandard 55mm Back Focus for Seamless Integration\u003c\/h3\u003e\n\u003cp\u003eThis reducer simplifies your imaging setup by providing the industry-standard 55mm back focus from its M48x0.75 camera connection threads. This spacing is designed to accommodate a wide range of DSLRs, mirrorless cameras, and dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e, with or without \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e and \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e. The robust mechanical design features a 65mm outer diameter and a total length of 95mm, integrating perfectly with the 61EDPH's \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the SharpStar 61EDPH 0.8x Reducer do?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt converts the SharpStar 61EDPH telescope into a faster photographic instrument. By reducing the focal ratio to \u003cstrong\u003ef\/4.5\u003c\/strong\u003e, it allows you to collect light more quickly, significantly shortening required exposure times for deep-sky astrophotography.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use this SharpStar reducer with a telescope other than the 61EDPH?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. This focal reducer is optically matched specifically for the SharpStar 61EDPH and 61EDPH II models. Using it with other telescopes will result in poor optical correction and will not produce a sharp, flat field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the 61EDPH 0.8x Reducer work with my full-frame camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer is designed to produce a flat, well-illuminated \u003cstrong\u003e44mm image circle\u003c\/strong\u003e, which is large enough to cover standard full-frame sensors (36mm x 24mm) without major vignetting, delivering sharp stars to the corners of your frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the 61EDPH 0.8x Reducer affect my imaging time on the Orion Nebula (M42)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eBy speeding up the telescope to f\/4.5, you can capture the same signal-to-noise ratio in roughly two-thirds of the time it would take at the native f\/5.5. For example, a 3-minute exposure at f\/5.5 would only require a 2-minute exposure with the reducer to achieve similar brightness, allowing you to capture more data in a single night.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eI use a filter wheel with my astronomy camera. Does the SharpStar 61EDPH reducer have enough back focus?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. It provides the standard \u003cstrong\u003e55mm of back focus\u003c\/strong\u003e from the base of its M48 threads. This is the industry-standard distance designed to accommodate common accessories like filter wheels, off-axis guiders, and spacers in your imaging train before the camera sensor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat threads are on the camera side of the 61EDPH reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe camera side of the reducer features a standard \u003cstrong\u003eM48x0.75 thread\u003c\/strong\u003e. This is the common \"2-inch filter thread\" standard used by most dedicated astronomy cameras and full-frame camera adapters.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eApplication\u003c\/td\u003e\n\u003ctd\u003eSharpStar 61EDPH \u0026amp; 61EDPH II\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/4.5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eThree-element air-spaced\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eFull-surface multi-layer coating\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection Thread\u003c\/td\u003e\n\u003ctd\u003eM48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOuter Diameter\u003c\/td\u003e\n\u003ctd\u003e65mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLength\u003c\/td\u003e\n\u003ctd\u003e95mm (including M48 thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.45kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eM63x1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e0.82x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSharpStar 61EDPH 0.8x Focal Reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSharpStar\/Askar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SharpStar Optics","offers":[{"title":"Default Title","offer_id":44967741063453,"sku":"SSO-SHRD61","price":307.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/SharpStar-61EDPH-Reducer-1__99821.1608945453.1280.1280.jpg?v=1684345755"},{"product_id":"sharpstar-76edph-0-8x-focal-reducer","title":"SharpStar 76EDPH 0.8x Focal Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eConverts 76EDPH to a fast f\/4.5 focal ratio\u003c\/li\u003e\n\u003cli\u003eProduces a 44mm image circle for full-frame sensors\u003c\/li\u003e\n\u003cli\u003eStandard 55mm back focus for easy camera integration\u003c\/li\u003e\n\u003cli\u003eThree-element air-spaced optical design\u003c\/li\u003e\n\u003cli\u003eAdds only 0.5kg to the imaging train\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eSharpStar 76EDPH 0.8x Focal Reducer\u003c\/h2\u003e\n\u003cp\u003eThe SharpStar 0.8x Focal Reducer is engineered specifically to convert the 76EDPH telescope into a fast f\/4.5 \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e, illuminating a full 44mm image circle for large-format sensors. This three-element reducer provides a standard 55mm back focus from its M48 threads, measures 77mm in length, and adds only 0.5kg to your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eTransform Your 76EDPH into an f\/4.5 Astrograph\u003c\/h3\u003e\n\u003cp\u003eBy reducing the native focal ratio of the 76EDPH to f\/4.5, this corrector significantly shortens required exposure times, allowing you to capture more signal on faint deep-sky objects in a single session. The dedicated optical design is precisely matched to the 76EDPH, ensuring sharp stars across the entire field of view.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDedicated Design:\u003c\/strong\u003e Mates directly to the 76EDPH \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e via an M74×1 thread for a secure, flex-free connection.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThree-Element Optics:\u003c\/strong\u003e The air-spaced triplet lens structure is fully multi-coated to maximize light transmission and suppress internal reflections for high-contrast images.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 44mm Image Circle for Full-Frame Sensors\u003c\/h3\u003e\n\u003cp\u003eThis reducer delivers a corrected, flat field across a 44mm image circle, which is large enough to accommodate full-frame (24x36mm) CMOS and CCD sensors without significant vignetting. This allows you to capture expansive targets like the Andromeda Galaxy (M31) or the Rho Ophiuchi cloud complex in a single frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e55mm Back Focus and 360° Rotation for Easy Framing\u003c\/h3\u003e\n\u003cp\u003eIntegration into your existing imaging setup is straightforward. The reducer provides the industry-standard 55mm of back focus from its M48x0.75 camera connection, accommodating most \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e, \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e, and \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e with minimal adapters. An integrated 360° \u003ca href=\"\/en-int\/collections\/rotators-and-tilt-adjusters\"\u003erotator\u003c\/a\u003e lets you perfectly frame your target without having to loosen the camera and risk optical tilt.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard M48 Threads:\u003c\/strong\u003e The camera-side connection uses M48 threads, which also accept standard 2\" astronomy filters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecise Composition:\u003c\/strong\u003e The built-in rotator allows for fine adjustments to your image orientation, a critical feature for capturing mosaics or aligning with celestial coordinates.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the 0.8x Reducer do for my SharpStar 76EDPH?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis reducer transforms your SharpStar 76EDPH into a faster, wider imaging instrument. It changes the focal ratio to \u003cstrong\u003ef\/4.5\u003c\/strong\u003e, which reduces your exposure times by about 33% and provides a wider field of view to capture larger celestial objects.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the 76EDPH 0.8x Reducer work with my full-frame camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer is designed to produce a flat, corrected \u003cstrong\u003e44mm image circle\u003c\/strong\u003e, which fully illuminates standard 35mm full-frame sensors (e.g., Sony IMX455 based cameras) without significant light fall-off at the corners.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect my camera and accessories to the SharpStar 76EDPH reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer has standard M48x0.75 threads on the camera side and provides \u003cstrong\u003e55mm of back focus\u003c\/strong\u003e. This is the standard distance for many DSLR\/mirrorless cameras with a \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e, as well as dedicated astronomy cameras when combined with filter wheels and off-axis guiders.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2\" filters with the 76EDPH 0.8x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the M48 threads on the camera side of the reducer are designed to accept standard \u003cstrong\u003e2\" (M48x0.75) filters\u003c\/strong\u003e. You can thread a filter directly onto the reducer before attaching your camera or filter wheel.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the f\/4.5 focal ratio help when imaging faint targets like the North American Nebula (NGC 7000) with the 76EDPH?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe North American Nebula (NGC 7000) is a large, faint emission nebula. The faster \u003cstrong\u003ef\/4.5 focal ratio\u003c\/strong\u003e allows your camera sensor to collect photons more quickly compared to the telescope's native f-ratio. This means you can achieve a strong signal-to-noise ratio with shorter sub-exposures, reducing the demands on your mount's tracking accuracy.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eI'm using an APS-C camera with my 76EDPH. Is the 44mm image circle of this reducer still beneficial?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. While an APS-C sensor is smaller than the \u003cstrong\u003e44mm image circle\u003c\/strong\u003e, using a reducer designed for a larger field ensures exceptional field flatness and star correction across your entire sensor. You will experience very tight, round stars from corner to corner, well within the \"sweet spot\" of the reducer's optical correction.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eApplication\u003c\/td\u003e\n\u003ctd\u003eSharpStar 76EDPH Astrograph\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/4.5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLens Design\u003c\/td\u003e\n\u003ctd\u003eThree-element air-spaced\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm from M48 thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLength\u003c\/td\u003e\n\u003ctd\u003e77mm (including M48 thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOuter Diameter\u003c\/td\u003e\n\u003ctd\u003e88mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eFull-surface multi-layer coating\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.5kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e0.82x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM74x1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSharpStar 76EDPH 0.8x Focal Reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eProduct Manuals\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDrivers \u0026amp; Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSharpStar\/Askar 1-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SharpStar Optics","offers":[{"title":"Default Title","offer_id":44967749583133,"sku":"SSO-76EDPHFR","price":371.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/SharpStar-76EDPH-Reducer-1__79028.1609101546.1280.1280.jpg?v=1684345784"},{"product_id":"sharpstar-94edph-0-8x-focal-reducer","title":"SharpStar 94EDPH 0.8x Focal Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e0.8x Focal Reduction for SharpStar 94EDPH\u003c\/li\u003e\n\u003cli\u003eCreates a Fast f\/4.4 Optical System\u003c\/li\u003e\n\u003cli\u003e4-Element Optical Design\u003c\/li\u003e\n\u003cli\u003e50mm Corrected Image Circle\u003c\/li\u003e\n\u003cli\u003eStandard 55mm Back Focus\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eSharpStar 94EDPH 0.8x Focal Reducer\u003c\/h2\u003e\n\u003cp\u003eThis dedicated 0.8x focal reducer transforms the SharpStar 94EDPH into a fast f\/4.4 imaging system, using a 4-element optical design to deliver a corrected 50mm image circle. The standard 55mm back focus simplifies camera and accessory integration, while the reducer itself has a maximum outside diameter of 88mm.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA Faster, Wider Field: The 4-Element Design for f\/4.4 Imaging\u003c\/h3\u003e\n\u003cp\u003eBy reducing the focal ratio to f\/4.4, this accessory significantly shortens required exposure times, allowing you to gather more signal on faint targets in a single session. The wider field of view also makes it possible to frame large celestial objects, like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000), in their entirety.\u003c\/p\u003e\n\u003cp\u003eThe 4-element optical layout is engineered to correct for optical aberrations across the field, ensuring that stars remain sharp and round from the center to the edge of the frame. This corrective power is essential for maintaining the high image quality of the 94EDPH's triplet objective.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFull-Frame Ready: 50mm Image Circle and 55mm Back Focus\u003c\/h3\u003e\n\u003cp\u003eThe reducer's optical design produces a fully illuminated and corrected 50mm image circle. This generous field is large enough to cover full-frame sensors (like the Sony a7 series or dedicated cameras with IMX455 sensors) without vignetting, maximizing the imaging potential of the telescope.\u003c\/p\u003e\n\u003cp\u003eA standard 55mm back focus distance simplifies the process of connecting most DSLRs, mirrorless cameras, and dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e along with their associated \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e or \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e. This industry-standard spacing ensures broad compatibility with your existing imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the SharpStar 94EDPH reducer cover my full-frame camera sensor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eYes.\u003c\/strong\u003e The reducer produces a \u003cstrong\u003e50mm image circle\u003c\/strong\u003e, which is more than large enough to fully illuminate a standard 36x24mm full-frame sensor without vignetting.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does this 0.8x reducer help when imaging a target like the Heart Nebula (IC 1805) with the 94EDPH?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer widens the field of view, allowing you to capture the entire expanse of large targets like the Heart Nebula in a single frame. It also speeds up the optics to \u003cstrong\u003ef\/4.4\u003c\/strong\u003e, reducing the exposure time needed to capture faint nebulosity.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the back focus of the SharpStar 94EDPH 0.8x reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe required back focus is \u003cstrong\u003e55mm\u003c\/strong\u003e. This is a standard distance for many imaging setups, making it easy to integrate with accessories like \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-rings\u003c\/a\u003e, filter wheels, and off-axis guiders.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the 4-element design in the SharpStar 94EDPH reducer do?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003e4-element design\u003c\/strong\u003e acts as both a reducer and a \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003efield flattener\u003c\/a\u003e. It is optically matched to the 94EDPH telescope to ensure stars are sharp and round across the entire 50mm image circle, correcting for field curvature and other off-axis aberrations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the final focal ratio of the SharpStar 94EDPH when using this reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis 0.8x reducer converts the SharpStar 94EDPH into a fast \u003cstrong\u003ef\/4.4\u003c\/strong\u003e imaging system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs this reducer compatible with other telescopes besides the SharpStar 94EDPH?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis reducer is specifically designed and optically matched for the SharpStar 94EDPH telescope. Using it with other telescopes is not recommended as it may not provide a fully corrected field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.8x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFinal Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/4.4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e4 Elements\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e50mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum Outer Diameter\u003c\/td\u003e\n\u003ctd\u003e88mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApplication\u003c\/td\u003e\n\u003ctd\u003eSharpStar 94EDPH\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side Connection\u003c\/td\u003e\n\u003ctd\u003eM74x1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection Thread\u003c\/td\u003e\n\u003ctd\u003eM48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLength\u003c\/td\u003e\n\u003ctd\u003e105mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.67kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSharpStar 94EDPH 0.8x Focal Reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSharpStar\/Askar 1-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SharpStar Optics","offers":[{"title":"Default Title","offer_id":44967749812509,"sku":"SSO-94EDPHFR","price":497.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/SharpStar-94EDPH-Reducer-1__36482.1609108367.1280.1280.jpg?v=1684345787"},{"product_id":"sharpstar-140ph-0-74x-focal-reducer","title":"SharpStar 140PH 0.74x Focal Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal ratio to f\/4.8\u003c\/li\u003e\n\u003cli\u003e0.74x reduction factor\u003c\/li\u003e\n\u003cli\u003e3-element optical design\u003c\/li\u003e\n\u003cli\u003e44mm corrected image circle\u003c\/li\u003e\n\u003cli\u003eStandard 55mm back focus\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eSharpStar 140PH 0.74x Focal Reducer\u003c\/h2\u003e\n\u003cp\u003eThe SharpStar 140PH 0.74x Focal Reducer is a dedicated 3-element corrector that converts the 140PH APO into a faster f\/4.8 \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e for wide-field imaging. It delivers a corrected 44mm image circle to illuminate full-frame sensors and maintains the standard 55mm back focus for easy integration with cameras, \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e, and \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eThe SharpStar 140PH at f\/4.8: A 0.74x Focal Reducer\u003c\/h3\u003e\n\u003cp\u003eBy shortening the telescope's effective focal length by a factor of 0.74x, this reducer widens the field of view, allowing you to capture large celestial targets in a single frame. The resulting f\/4.8 focal ratio significantly cuts down required exposure times, enabling you to collect more signal on faint nebulae and galaxies in less time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e44mm Image Circle \u0026amp; 55mm Back Focus for Full-Frame Cameras\u003c\/h3\u003e\n\u003cp\u003eEngineered for modern sensors, this reducer projects a fully illuminated and corrected 44mm image circle, providing edge-to-edge sharpness on full-frame (36x24mm) CMOS and CCD cameras. The industry-standard 55mm back focus simplifies your imaging train; simply add your camera and standard \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e or filter wheel setup to achieve perfect spacing without complex calculations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the SharpStar 140PH 0.74x Reducer do to my telescope's performance?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis reducer makes your SharpStar 140PH telescope \"faster\" by changing its focal ratio to \u003cstrong\u003ef\/4.8\u003c\/strong\u003e. This allows you to capture more light in shorter exposures and provides a wider field of view, which is ideal for large deep-sky objects.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 44mm image circle of the 140PH Reducer large enough for my full-frame camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The \u003cstrong\u003e44mm image circle\u003c\/strong\u003e is specifically designed to fully illuminate the 43.3mm diagonal of a standard full-frame sensor (e.g., Sony IMX455 or full-frame DSLR sensors) with corrected stars to the corners.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I achieve the correct 55mm back focus with the SharpStar 140PH Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003e55mm back focus\u003c\/strong\u003e is measured from the rear flange of the reducer to your camera's sensor. This is a standard distance. For a DSLR, a standard 48mm T-ring typically provides the correct spacing. For dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e, you use a combination of included camera spacers, a filter wheel, and an off-axis guider to reach the 55mm total distance.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this 0.74x reducer work with telescopes other than the SharpStar 140PH?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this reducer is optically matched specifically for the SharpStar 140PH APO triplet \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractor\u003c\/a\u003e. Using it with other telescopes will likely result in poor image quality, field curvature, and other optical aberrations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the SharpStar 140PH 0.74x Reducer help when imaging the Andromeda Galaxy (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Andromeda Galaxy (M31) is a very large target. The wider field of view provided by the \u003cstrong\u003e0.74x reducer\u003c\/strong\u003e allows you to capture the entire galaxy and its companions in a single frame with the 140PH. The faster \u003cstrong\u003ef\/4.8\u003c\/strong\u003e optics also let you capture faint outer dust lanes with shorter individual exposures.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use a filter wheel with the SharpStar 140PH reducer and my camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The \u003cstrong\u003e55mm back focus\u003c\/strong\u003e distance is designed to accommodate common accessories. For example, if your camera has a 17.5mm flange distance and your filter wheel is 20mm thick, you would need a 17.5mm spacer (17.5 + 20 + 17.5 = 55mm) to achieve perfect focus.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescope\u003c\/td\u003e\n\u003ctd\u003eSharpStar 140PH APO\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.74x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResulting Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/4.8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e3 Elements\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum Outer Diameter\u003c\/td\u003e\n\u003ctd\u003e94mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eM88x1 (dealer)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-side connection\u003c\/td\u003e\n\u003ctd\u003eM48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSharpStar 140PH 0.74x Focal Reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Drivers and Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSharpStar\/Askar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SharpStar Optics","offers":[{"title":"Default Title","offer_id":44967753580829,"sku":"SSO-140PHFR","price":615.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/SharpStar-140PH-Reducer-1__05468.1609108728.1280.1280.jpg?v=1684345788"},{"product_id":"askar-2-5-f-3-9-full-frame-reducer-for-fra400-and-fra500","title":"Askar 2.5\" F\/3.9 Full Frame Reducer for FRA400 and FRA500","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal ratio to a fast f\/3.9\u003c\/li\u003e\n\u003cli\u003e0.7x reduction factor\u003c\/li\u003e\n\u003cli\u003e44mm image circle fully illuminates full-frame sensors\u003c\/li\u003e\n\u003cli\u003eStandard 55mm back focus for easy camera connection\u003c\/li\u003e\n\u003cli\u003eIntegrated M48x0.75 thread for 2\" filters\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 2.5\" F\/3.9 Full Frame Reducer for FRA400 and FRA500\u003c\/h2\u003e\n\u003cp\u003eThe Askar 2.5\" F\/3.9 Full Frame Reducer transforms your \u003ca href=\"\/en-int\/products\/askar-fra400-72mm-f-5-6-quintuplet-apo\"\u003eAskar FRA400\u003c\/a\u003e or \u003ca href=\"\/en-int\/products\/askar-fra500-90mm-f-5-6-quintuplet-apo\"\u003eFRA500\u003c\/a\u003e \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e into a significantly faster imaging system, achieving a final focal ratio of f\/3.9 with its 0.7x reduction factor. This 3-element, air-spaced optical design illuminates a full 44mm image circle, providing edge-to-edge sharpness on full-frame sensors while maintaining a standard 55mm back focus for straightforward integration of your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e0.7x Reduction for an f\/3.9 System\u003c\/h3\u003e\n\u003cp\u003eBy shortening the effective focal length of your telescope, this reducer dramatically increases the speed of your optical system. On an Askar FRA400, the focal length is reduced from 400mm to just 280mm, changing the native f\/5.6 ratio to a swift f\/3.9. This speed increase allows you to capture the same amount of signal in roughly half the time, maximizing your data acquisition during short imaging windows.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 44mm Corrected Image Circle for Full-Frame Sensors\u003c\/h3\u003e\n\u003cp\u003eEngineered specifically for large-format sensors, this reducer delivers a fully-corrected 44mm image circle. This ensures that you can utilize the entire field of view of your full-frame DSLR, mirrorless, or dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy camera\u003c\/a\u003e without significant vignetting or loss of star quality at the corners. It turns your astrograph into a true wide-field instrument capable of capturing vast nebulae and star fields in a single frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e55mm Back Focus and Integrated 2\" Filter Threads\u003c\/h3\u003e\n\u003cp\u003eAskar designed this reducer for seamless integration into modern imaging setups. It features the industry-standard 55mm back focus, allowing you to connect most cameras and \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e with standard adapters. An integrated M48x0.75 thread provides a secure attachment point for any 2\" filter, enabling the use of light pollution or \u003ca href=\"\/en-int\/collections\/narrowband-filters\"\u003enarrowband filters\u003c\/a\u003e without adding complexity to your optical train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the Askar F\/3.9 reducer do for my FRA400 or FRA500?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis 0.7x reducer shortens your telescope's focal length, making it optically \"faster.\" For the FRA400, it changes the focal length to 280mm and the focal ratio to f\/3.9. This results in a wider field of view and significantly shorter exposure times needed to capture faint deep-sky objects.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use full-frame cameras with the Askar F\/3.9 reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer is specifically designed to produce a corrected \u003cstrong\u003e44mm image circle\u003c\/strong\u003e, which is large enough to cover standard full-frame sensors (typically 43.3mm diagonal) without vignetting. This ensures sharp stars across the entire frame of your large-format camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs it difficult to connect my camera to the Askar F\/3.9 reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, connection is straightforward. The reducer requires a standard \u003cstrong\u003e55mm back focus\u003c\/strong\u003e from the rear mounting flange to your camera sensor. This is the same spacing used by most DSLRs with a \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e and many dedicated astronomy cameras with their included spacers, making it easy to achieve the correct distance for optimal performance.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does a 0.7x reducer affect my exposure times?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA faster focal ratio gathers light more quickly. Moving from f\/5.6 (on the FRA400) to f\/3.9 means your exposure times can be cut by more than half to achieve the same image brightness. A 5-minute sub-exposure at f\/5.6 is roughly equivalent to a 2.5-minute sub at f\/3.9.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I image the entire North America Nebula (NGC 7000) with an FRA400 and this reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, this setup is ideal for such large targets. With the reducer, an FRA400 has a 280mm focal length. Paired with a full-frame sensor (like a Sony a7 series or ZWO ASI6200), this provides a field of view of approximately 7.3° x 4.9°, which is more than enough to comfortably frame the entire North America Nebula (NGC 7000) and the neighboring Pelican Nebula (IC 5070).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat's the best way to use 2\" filters with the Askar F\/3.9 reducer on my FRA500?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer has a built-in M48x0.75 thread for attaching a standard 2\" mounted filter. Askar does not state on which side of the reducer the thread sits, so check before building your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct\u003c\/td\u003e\n\u003ctd\u003eF\/3.9 Full Frame Reducer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatibility\u003c\/td\u003e\n\u003ctd\u003eAskar FRA400, Askar FRA500\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.7x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResulting Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/3.9\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e3-element, air-spaced\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thread\u003c\/td\u003e\n\u003ctd\u003eM48 x 0.75 (for 2\" filters)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Outer Diameter\u003c\/td\u003e\n\u003ctd\u003e72mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 2.5\" F\/3.9 Full Frame Reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software \u0026amp; Drivers\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":44967778976029,"sku":"ASK-ASKAR7256RD","price":384.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Askar-FRA400FR-1__39150.1610302783.1280.1280.jpg?v=1684345839"},{"product_id":"askar-3-f-3-9-full-frame-reducer-for-fra600","title":"Askar 3\" F\/3.9 Full Frame Reducer for FRA600","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces FRA600 focal ratio to F\/3.9\u003c\/li\u003e\n\u003cli\u003eDesigned for full-frame sensors\u003c\/li\u003e\n\u003cli\u003eMaintains a standard 55mm backfocus\u003c\/li\u003e\n\u003cli\u003eFeatures integrated M48 (2-inch) filter threads\u003c\/li\u003e\n\u003cli\u003e4-element optical design, 0.7x reduction to 420mm\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 3\" F\/3.9 Full Frame Reducer for FRA600\u003c\/h2\u003e\n\u003cp\u003eDesigned exclusively for the \u003ca href=\"\/en-int\/products\/askar-fra600-108mm-f-5-6-quintuplet-apo\"\u003eAskar FRA600\u003c\/a\u003e \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e, this 3\" full-frame reducer transforms the telescope into a significantly faster F\/3.9 optical system. By reducing the focal length, this corrector provides a much wider field of view and cuts down exposure times, maintaining a standard 55mm backfocus for easy camera integration.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eTransform Your FRA600 into an F\/3.9 Astrograph\u003c\/h3\u003e\n\u003cp\u003eThis reducer converts your Askar FRA600 into a powerful, wide-field imaging instrument. The resulting F\/3.9 focal ratio allows you to gather significantly more light in a shorter period, enabling deeper exposures on faint nebulae and galaxies without taxing your mount's tracking accuracy over long sub-exposures. The wider field of view is essential for framing large-scale celestial objects in their entirety.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e55mm Backfocus and Full-Frame Illumination\u003c\/h3\u003e\n\u003cp\u003eEngineered for modern astrophotography, the reducer provides the industry-standard 55mm backfocus. This simplifies the process of connecting your full-frame DSLR, mirrorless, or dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy camera\u003c\/a\u003e, ensuring you can achieve perfect spacing with common M48 rings and accessories. Its optical design is optimized to fully illuminate a full-frame sensor, delivering sharp, well-corrected stars across the entire image. For added convenience, the reducer includes built-in M48x0.75 threads for easy installation of 2-inch filters into your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main benefit of using the Askar F\/3.9 reducer with my FRA600?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary benefit is speed. By converting your FRA600 to F\/3.9, you can dramatically shorten exposure times. This allows you to collect the same amount of data in less time, improving your efficiency and resulting in images with a higher signal-to-noise ratio. It also provides a wider field of view, perfect for large targets.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes this Askar reducer maintain a flat field with full-frame sensors on the FRA600?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the Askar 3\" F\/3.9 reducer is specifically designed as a \"full frame\" corrector for the FRA600. Its multi-element optical system is engineered to deliver a flat, corrected field that illuminates large sensors, ensuring sharp stars from the center to the corners of your image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2-inch filters with the Askar F\/3.9 reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. The reducer features integrated \u003cstrong\u003eM48x0.75 threads\u003c\/strong\u003e, which is the standard for 2-inch astronomy filters. You can directly screw in your favorite light pollution, narrowband, or \u003ca href=\"\/en-int\/collections\/lrgb-filters\"\u003eLRGB filters\u003c\/a\u003e without needing a separate \u003ca href=\"\/en-int\/collections\/filter-wheels-and-drawers\"\u003efilter drawer\u003c\/a\u003e or wheel in some configurations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the backfocus of the Askar F\/3.9 reducer for the FRA600?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer is designed with a standard \u003cstrong\u003e55mm backfocus\u003c\/strong\u003e. This is measured from the rear flange of the reducer to the camera sensor. This standard distance makes it compatible with most dedicated astronomy cameras and DSLR\/mirrorless cameras when using the appropriate M48 \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Askar F\/3.9 reducer work with a camera and filter wheel combination on my FRA600?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, as long as your total imaging train length meets the 55mm backfocus requirement. You will need to account for the thickness of your \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheel\u003c\/a\u003e, \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guider\u003c\/a\u003e (if any), and all adapters between the reducer and your camera's sensor. The standard 55mm spacing provides enough room for common accessory combinations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Askar F\/3.9 reducer help when imaging the Andromeda Galaxy (M31) with the FRA600?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Andromeda Galaxy (M31) is a very large target. The standard FRA600 might frame the core tightly, but this F\/3.9 reducer widens the field of view significantly. This allows you to capture the full expanse of M31, including its faint outer arms and satellite galaxies M32 and M110, all within a single, well-composed shot on a full-frame sensor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eKind\u003c\/td\u003e\n\u003ctd\u003eReducer (full frame)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification factor\u003c\/td\u003e\n\u003ctd\u003e0.7x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired back focus\u003c\/td\u003e\n\u003ctd\u003e55 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e44 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for (scopes \/ focal range)\u003c\/td\u003e\n\u003ctd\u003eAskar FRA600 (420 mm at f\/3.9)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eElements\u003c\/td\u003e\n\u003ctd\u003e4 elements, air-spaced\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-side connection\u003c\/td\u003e\n\u003ctd\u003eM48x0.75 (2\" filter thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned For\u003c\/td\u003e\n\u003ctd\u003eAskar FRA600 (600mm f\/5.6 -\u0026gt; 420mm f\/3.9)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 3\" F\/3.9 Full Frame Reducer for FRA600\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software \u0026amp; Drivers\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":44967779008797,"sku":"ASK-ASKAR656RD","price":615.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Askar-FRA600FR-1__09035.1610302990.1280.1280.jpg?v=1684345841"},{"product_id":"william-optics-adjustable-flat6aiii-for-flt91","title":"William Optics Adjustable Flat6AIII for FLT91","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eDedicated Field Flattener for the William Optics FLT91 Telescope\u003c\/li\u003e\n\u003cli\u003eCorrects Field Curvature for Pinpoint Stars Edge-to-Edge\u003c\/li\u003e\n\u003cli\u003eIntegrated Adjustment Ring for Precise Back Focus Tuning\u003c\/li\u003e\n\u003cli\u003eIncludes Custom Adapter for a Secure Connection to the FLT91\u003c\/li\u003e\n\u003cli\u003eEnables Full-Frame Astrophotography with the FLT91\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eWilliam Optics Adjustable Flat6AIII for FLT91\u003c\/h2\u003e\n\u003cp\u003eOwners of the \u003ca href=\"\/en-int\/products\/william-optics-fluorostar-91\"\u003eWilliam Optics Fluorostar 91\u003c\/a\u003e \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractor\u003c\/a\u003e can achieve a perfectly flat photographic field with the dedicated Adjustable Flat6AIII corrector. This optical system is engineered specifically for the FLT91 to eliminate field curvature, rendering stars as sharp, pinpoint sources from the center to the very edge of the frame. The package includes the Flat6AIII flattener and the specific adapter ring for a seamless, rigid connection, with an integrated adjustment mechanism for precise back focus control.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAchieve a Perfectly Flat Field with the FLT91\u003c\/h3\u003e\n\u003cp\u003eWhile the FLT91 provides exceptional color correction, like all fast refractors, its native focal plane has a slight curvature. For visual use, this is unnoticeable, but for astrophotography, it results in slightly elongated stars in the corners of an image. The Flat6AIII is the matched solution, designed to counteract this specific optical characteristic, ensuring your images have a professional, uniformly sharp appearance across even large full-frame sensors.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eIntegrated Adjustment for a Versatile Imaging Train\u003c\/h3\u003e\n\u003cp\u003eThe \"Adjustable\" design of the Flat6AIII is its key mechanical advantage. It features a built-in, rotatable adjustment ring that allows you to dial in the perfect sensor-to-flattener distance for your specific camera, \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheel\u003c\/a\u003e, or \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guider\u003c\/a\u003e setup. This eliminates the trial-and-error of finding the right combination of extension tubes and spacers, saving you valuable time in the field. This unit ships with the necessary adapter ring, ensuring a direct, secure, and perfectly centered attachment to the FLT91's \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e drawtube for a completely rigid imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the purpose of the William Optics Adjustable Flat6AIII for the FLT91?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003eWilliam Optics Adjustable Flat6AIII\u003c\/strong\u003e is a dedicated field flattener designed for the FLT91 \u003ca href=\"\/en-int\/collections\/apochromatic-refractors\"\u003eapo refractor\u003c\/a\u003e. Its primary function is to correct for the natural field curvature of the telescope's optics, ensuring that stars are sharp and pinpoint across the entire image sensor, from the center to the corners.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is the \"adjustable\" feature of the Flat6AIII important for my FLT91 setup?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe adjustable mechanism allows you to precisely set the back focus distance between the flattener's optics and your camera's sensor. This is critical because different cameras, filter wheels, and off-axis guiders create different optical path lengths. The adjustability ensures you can achieve perfect correction with your specific imaging train without needing a collection of separate spacers.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need a separate adapter to connect the Flat6AIII to my William Optics FLT91?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. This product package includes both the Flat6AIII flattener and the specific adapter ring required for a direct and secure connection to the William Optics FLT91 telescope's focuser.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Adjustable Flat6AIII help when imaging large targets like the Andromeda Galaxy (M31) with the FLT91?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhen imaging a large object like the Andromeda Galaxy (M31), you want the entire field to be perfect. Without the \u003cstrong\u003eFlat6AIII\u003c\/strong\u003e, the stars at the edges of the galaxy might appear soft or elongated. By flattening the field, this corrector ensures that every star in your frame is a sharp point, resulting in a much more professional and aesthetically pleasing final image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Flat6AIII a focal reducer as well as a flattener?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The Flat6AIII is a 0.8x reducer and flattener. It flattens the field and also shortens the FLT91's focal length, giving a faster f-ratio.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Adjustable Flat6AIII for FLT91 work with both DSLR and dedicated astronomy cameras?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The adjustable back focus is specifically designed to accommodate the different flange distances of various cameras. Whether you are using a DSLR with a 48mm (M48) \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e or a dedicated \u003ca href=\"\/en-int\/collections\/deep-sky-cameras\"\u003ecooled astronomy camera\u003c\/a\u003e with a filter wheel, you can tune the spacing for optimal optical performance.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Name\u003c\/td\u003e\n\u003ctd\u003eWilliam Optics Adjustable Flat6AIII for FLT91\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatibility\u003c\/td\u003e\n\u003ctd\u003eWilliam Optics FLT91 Apochromatic Refractor\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Function\u003c\/td\u003e\n\u003ctd\u003eField Flattener \/ Reducer (0.8x)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eKey Feature\u003c\/td\u003e\n\u003ctd\u003eIntegrated Adjustable Back Focus\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConnection\u003c\/td\u003e\n\u003ctd\u003eIncludes dedicated adapter for FLT91 focuser\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eM92 (FLT91 focuser)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-side connection\u003c\/td\u003e\n\u003ctd\u003eM48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eElements\u003c\/td\u003e\n\u003ctd\u003e3 elements in 3 groups\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003e0.8x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003eAdjustable (integrated back focus adjustment)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eFlat6AIII reducer-flattener\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eFLT91 (M92) adapter ring\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967782187293,"sku":"WO-P-FLAT6AIII-M92","price":456.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/William-Optics-Adjustable-Flat6AIII-P-FLAT6AIII-1__21819.1596133240.1280.1280__76625.1614355641.1280.1280.jpg?v=1684345861"},{"product_id":"ts-optics-0-67x-reducer-for-rc-telescopes-2","title":"TS-Optics 0.67x Reducer for RC Telescopes - 2\"","description":"\u003c!-- more --\u003e\u003cp\u003e\u003cb itemprop=\"description\"\u003eThe 2\" CCD compressor reduces the focal length of telescopes with the factor 0.67x, thus allowing significantly shorter exposure times.\u003c\/b\u003e\u003c\/p\u003e\u003cp\u003e♦ The focal reducer is perfectly suitable for RC telescope. It also works good with Celestron EHD or Meade ACF telescopes or with refractors up to the focal ratio F\/9\u003cbr\u003e\u003cbr\u003e♦ The image field of DSLR cameras up to APS-C format is illuminated - full illumination up to 29 mm\u003cbr\u003e\u003cbr\u003e♦ Easy connection to the telescope via 2\" barrel\u003cbr\u003e\u003cbr\u003e♦ Optimal working distance from the M48x0.75 thread to the camera sensor is 85 mm - enough space for accessories like off-axis guider or filter wheel\u003cbr\u003e\u003cbr\u003e♦ 2\" filter thread at the telescope side\u003c\/p\u003e\u003ch2\u003eTS-Optics CCD telecompressor for Ritchey-Chrétien and other F\/18 to F\/8 telescopes\u003c\/h2\u003e\u003cp\u003e\u003cspan\u003eThe TS telecompressor CCD47 was developed for reducing the focal length of RC (Ritchey-Chrétien) telescopes. Practical tests have also shown an excellent suitability for all telescopes with flat field, like apochromats with built-in corrector lens, Celestron EHD or Meade ACF telescopes, thus the most flat-field telescopes. We especially recommend the compressor for the GSO \/ TS Optics \/ AstroTec Ritchey-Chrétien telescopes.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003c\/p\u003e\u003ch2\u003eThe features of the CCD47 telecompressor:\u003c\/h2\u003e\u003cp\u003e\u003cbr\u003e\u003cspan\u003e♦ Barrel size is 2\" - easy connection to all focusers with 2\" receptacle\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e♦ With thread for 2\" filters at the telescope side\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e♦ Camer aconnection via M48x0.75 thread\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e♦ Optimal working distance from the connection thread: 85 mm to the camera sensor. Between 70-90 mm, the results are very good.\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e♦ Reduction by 0.67x - an RC with F\/8 changes to fast f\/5.3. A telescope with F\/10 still turns into F\/6.7. The exposure time will be more than halved!\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e♦ An illuminated image field of 29 mm allows using all camera sensors up to APS-C format.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003c\/p\u003e\u003ch2\u003eAdapter recommendations:\u003c\/h2\u003e\u003cp\u003e\u003cspan\u003eWith the long working distance, adaptation of all common cameras, no matter whether CCD or DSLR, is possible without any problems. Some examples of applications:\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003e♦ DSLR camera - adaption via M48: TSVF230 and then the matching adapter from M48 to the camera, like the SKM48-EOS for connecting a Canon EOS\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003e♦ CCD cameras via T2 connection: two adapters are possible for reducing the M48 thread to T2:\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eTSFA2 - adapter to T2 with 38.2 mm length. This is used for bridging optical path.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eTSM48-T2 - a short adapter with only 3.5 mm length. This is applied if accessories like off-axis guider and filter wheels should be used.\u003c\/span\u003e\u003c\/p\u003e\u003ctable cellpadding=\"4\"\u003e\u003ctbody\u003e\n\u003ctr class=\"bgltblue\"\u003e\n\u003ctd class=\"pr9\"\u003e\n\u003cb\u003eBarrel size\u003c\/b\u003e:\u003c\/td\u003e\n\u003ctd\u003e2\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"stpage-bg\"\u003e\n\u003ctd class=\"pr9\"\u003e\n\u003cb\u003eFilter thread\u003c\/b\u003e:\u003c\/td\u003e\n\u003ctd\u003e2\" filter thread at the telescope side\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"bgltblue\"\u003e\n\u003ctd class=\"pr9\"\u003e\n\u003cb\u003eCamera connector\u003c\/b\u003e:\u003c\/td\u003e\n\u003ctd\u003eM48x0.75 thread (male, 5 mm long)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"stpage-bg\"\u003e\n\u003ctd class=\"pr9\"\u003e\n\u003cb\u003eBody length\u003c\/b\u003e:\u003c\/td\u003e\n\u003ctd\u003e29.2 mm (w\/o male thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"bgltblue\"\u003e\n\u003ctd class=\"pr9\"\u003e\n\u003cb\u003eWorking distance\u003c\/b\u003e:\u003c\/td\u003e\n\u003ctd\u003eBetween 70-90 mm - optimal results are achieved at approx. 85 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"stpage-bg\"\u003e\n\u003ctd class=\"pr9\"\u003e\n\u003cb\u003eFactor\u003c\/b\u003e:\u003c\/td\u003e\n\u003ctd\u003e0.67x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"bgltblue\"\u003e\n\u003ctd class=\"pr9\"\u003e\n\u003cb\u003eClear aperture\u003c\/b\u003e:\u003c\/td\u003e\n\u003ctd\u003e44 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"stpage-bg\"\u003e\n\u003ctd class=\"pr9\"\u003e\n\u003cb\u003eCoating\u003c\/b\u003e:\u003c\/td\u003e\n\u003ctd\u003eBest possible coating - guaranteed no reflexes or ghost images\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"bgltblue\"\u003e\n\u003ctd class=\"pr9\"\u003e\n\u003cb\u003eIllumination at f\/8\u003c\/b\u003e:\u003c\/td\u003e\n\u003ctd\u003eD=29 mm fully illuminated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e","brand":"TS-Optics","offers":[{"title":"Default Title","offer_id":44967988298013,"sku":"TS-CCD47","price":399.0,"currency_code":"CAD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/TS-0-67x-Reducer-RC-CCD47__64846.1645046285.1280.1280.jpg?v=1684347665"},{"product_id":"starizona-hyperstar-v4-for-celestron-8","title":"Starizona HyperStar V4 for Celestron 8\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eConverts Celestron 8\" SCTs to an f\/1.9 imaging system\u003c\/li\u003e\n\u003cli\u003e390mm focal length provides a massive 4.1° field of view\u003c\/li\u003e\n\u003cli\u003eIlluminates sensors up to 28mm in diagonal\u003c\/li\u003e\n\u003cli\u003eCompatible with standard C8 and EdgeHD 8 optical tubes\u003c\/li\u003e\n\u003cli\u003eIncludes M42 camera adapter for 17.5mm backfocus\u003c\/li\u003e\n\u003cli\u003eWeighs less than 1 lb for easy balancing\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eStarizona HyperStar V4 for Celestron 8\"\u003c\/h2\u003e\n\u003cp\u003eThe Starizona HyperStar V4 for Celestron 8\" transforms your SCT into a powerful f\/1.9 prime-focus \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e with a 390mm focal length. This system illuminates sensors up to 28mm across, delivering a massive, coma-free 4.1° field of view. By replacing the secondary mirror, it works 25 times faster than the native f\/10 configuration, enabling deep-sky imaging with dramatically shorter exposures.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eStarizona HyperStar 8: An f\/1.9 Prime-Focus Imaging System\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar 8 lens assembly replaces the secondary mirror on any Fastar-compatible 8\" Celestron \u003ca href=\"\/en-int\/collections\/schmidt-cassegrain-telescopes\"\u003eSchmidt-Cassegrain telescope\u003c\/a\u003e. This conversion places your camera at the prime focus of the telescope's primary mirror, creating an incredibly fast, wide-field instrument ideal for deep-sky astrophotography. The result is a 390mm f\/1.9 system that captures vast targets like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000) in a single frame.\u003c\/p\u003e\n\u003cp\u003eThis design is engineered for imagers who want to capture high-quality data in a fraction of the time required by traditional setups. No guiding and no \u003ca href=\"\/en-int\/collections\/equatorial-wedges\"\u003eequatorial wedge\u003c\/a\u003e are required. The HyperStar V4 is a complete, self-contained optical system designed and built in Tucson, Arizona.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e25x Faster Imaging: The f\/1.9 Advantage for Unguided Exposures\u003c\/h3\u003e\n\u003cp\u003eThe defining feature of the HyperStar system is its speed. By converting the C8 from f\/10 to f\/1.9, the HyperStar 8 is 25 times faster than the stock f\/10 telescope, so each sub-exposure can be a small fraction of the length needed at f\/10.\u003c\/p\u003e\n\u003cp\u003eShort sub-exposures make tracking errors far less critical, which is why no guiding and no equatorial wedge are required, including on fork-mounted \u003ca href=\"\/en-int\/collections\/alt-azimuth-mounts\"\u003ealt-azimuth\u003c\/a\u003e telescopes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eHyperStar 8 vs. Native f\/10: A 25x Speed Comparison\u003c\/h3\u003e\n\u003cp\u003eOperating a Celestron 8\" SCT in its native f\/10 configuration yields a focal length of around 2032mm, ideal for high-magnification views of planets and small deep-sky objects. The HyperStar 8 offers a completely different imaging experience by converting the same telescope into a 390mm f\/1.9 astrograph.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocal Ratio:\u003c\/strong\u003e f\/1.9 with HyperStar versus f\/10 natively. That is 25 times faster.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField of View:\u003c\/strong\u003e The HyperStar delivers up to a 4.1° field, wide enough to encompass huge emission nebulae and star clusters. The native f\/10 field is typically less than one degree, suited for close-ups.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocal Length:\u003c\/strong\u003e 390mm with HyperStar versus ~2032mm natively. The short focal length of the HyperStar is far more forgiving of tracking errors and wind, making guiding less critical or even unnecessary.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrimary Use Case:\u003c\/strong\u003e The HyperStar excels at capturing large deep-sky objects quickly. The native f\/10 configuration is superior for imaging the Moon, planets like Jupiter and Saturn, and resolving fine detail in smaller galaxies and planetary nebulae.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 4.1° Coma-Free Field for Sensors up to 28mm\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar V4 optics are engineered to deliver a flat, coma-free image circle across a field of view up to 4.1° wide. The fully multi-coated lens system corrects the image at the prime focus of the Schmidt-Cassegrain for a coma-free, flat field.\u003c\/p\u003e\n\u003cp\u003eThe system is optimized for modern \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e, illuminating sensors with a diagonal up to 28mm. This accommodates a wide range of popular APS-C and smaller format CMOS and CCD cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFor 8\" Celestron SCTs: Fastar and EdgeHD Compatibility\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar V4 for C8 is designed for any Celestron 8\" SCT that is \"Fastar-compatible,\" meaning it has a removable secondary mirror assembly. For older, non-Fastar tubes, a separate conversion kit is available from Starizona to make them HyperStar-ready.\u003c\/p\u003e\n\u003cp\u003eThis model is also fully compatible with Celestron's EdgeHD 8\" optical tubes. The package includes a specific EdgeHD Adapter Ring that fits the same HyperStar unit to EdgeHD 8 optical tubes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e17.5mm Backfocus: The Standard M42 Adapter for Cooled Cameras\u003c\/h3\u003e\n\u003cp\u003eAchieving correct sensor spacing is critical at f\/1.9. The HyperStar 8 ships with a Standard Camera Adapter that is precisely machined to place the sensor at the required 17.5mm backfocus distance. This adapter features standard M42 male T-threads, which covers most popular cooled astrocameras.\u003c\/p\u003e\n\u003cp\u003eThis pre-set distance eliminates the need for guesswork or complex spacer combinations. You simply thread your camera onto the adapter, and the critical backfocus is set. For cameras with different backfocus requirements or thread sizes (such as DSLRs or those requiring M54 threads), a range of alternative adapters are available separately.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eSingle 2\" Filter Cell and Optional M42\/M54 Filter Slider\u003c\/h3\u003e\n\u003cp\u003eThe included Standard Camera Adapter accepts one standard 2\" (M48) mounted filter. This is ideal for use with a light pollution, IR-cut, or multi-band \u003ca href=\"\/en-int\/collections\/nebula-filters\"\u003enebula filter\u003c\/a\u003e, allowing you to capture filtered data with a one-shot-color camera without additional accessories.\u003c\/p\u003e\n\u003cp\u003eFor imagers who need to swap between multiple filters, such as LRGB or narrowband, an optional Filter Slider Upgrade is available. This accessory replaces the standard adapter and provides a drawer system for quick filter changes. The optional slider includes both M42 and M54 male top plates, offering greater flexibility for connecting different cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFrom f\/10 to f\/1.9 in Minutes: Reversible Installation\u003c\/h3\u003e\n\u003cp\u003eConverting your C8 for HyperStar imaging is a straightforward, reversible process. The secondary mirror is unthreaded from the corrector plate and stored securely in the included Secondary Mirror Holder. The HyperStar lens assembly then threads into its place. Reinstalling the secondary mirror returns the telescope to its native f\/10 configuration.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eIndependent Camera Rotation and Precision Collimation\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar V4 design includes features for precise final adjustments. Independent camera rotation lets you turn the camera to frame your target without moving the lens.\u003c\/p\u003e\n\u003cp\u003eThe lens assembly also features adjustable collimation screws. These adjustments let you fine-tune the optical alignment of the lens.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eUnder 1 lb: Balancing the HyperStar on Your Mount\u003c\/h3\u003e\n\u003cp\u003eWeighing less than 1 lb, the HyperStar 8 lens and a typical astronomy camera add minimal weight to the front of the telescope. On a German equatorial mount, balance is easily achieved by sliding the optical tube forward in its saddle. A counterweight is not needed where the tube can slide in the saddle.\u003c\/p\u003e\n\u003cp\u003eFor fork-mounted (alt-azimuth) telescopes where the tube cannot slide, a separate HyperStar Counterweight (sold separately) fits into the 1.25\" visual back at the rear of the telescope to balance the lens and camera on the front.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAchieving Critical Focus at an f\/1.9 Focal Ratio\u003c\/h3\u003e\n\u003cp\u003eThe extremely fast f\/1.9 focal ratio creates a very narrow critical focus zone, meaning that precise focus is essential for sharp images. While challenging, achieving this is straightforward with modern tools. A \u003ca href=\"\/en-int\/collections\/focusing-masks\"\u003eBahtinov mask\u003c\/a\u003e is the most common method, providing a clear and unambiguous diffraction pattern that indicates perfect focus.\u003c\/p\u003e\n\u003cp\u003eAutomated focusing systems, combined with software that measures star size (FWHM), are also highly effective. The key is to make very small, deliberate adjustments with the telescope's focuser.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e3.5\" Body, Made in the USA: Build and Included Hardware\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar V4 lens assembly measures just 3.5\" in length (without the camera adapter) and 3.0\" in diameter. It has a black anodized finish and is designed and built in Tucson, Arizona.\u003c\/p\u003e\n\u003cp\u003eThe complete package includes everything needed to convert your telescope:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHyperStar 8 (C8 v4) Lens:\u003c\/strong\u003e The core f\/1.9 optical assembly.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEdgeHD Adapter Ring:\u003c\/strong\u003e Ensures compatibility with Celestron EdgeHD 8 OTAs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard Camera Adapter:\u003c\/strong\u003e Provides M42 threads and sets the 17.5mm backfocus.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSecondary Mirror Holder:\u003c\/strong\u003e A protective housing for your SCT's secondary mirror when not in use.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Starizona HyperStar V4 work with my older, non-Fastar C8?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, not out of the box. The HyperStar 8 requires a \"Fastar-compatible\" secondary mirror holder that can be removed. However, Starizona offers a C8 Conversion Kit (sold separately) that can upgrade many older, non-Fastar optical tubes to be compatible with the HyperStar system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the HyperStar V4 for C8 attach to an EdgeHD 8 telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe package includes the EdgeHD Adapter Ring, which fits the same HyperStar 8 unit to EdgeHD 8 optical tubes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use my DSLR camera with the HyperStar V4 for C8?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNot with a mirrored DSLR: mirrored DSLR adapters do not work on the HyperStar C8, and full-frame cameras cannot attach to it. The included Standard Camera Adapter is set for cameras with 17.5mm of backfocus and M42 threads; other camera adapters are sold separately.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the HyperStar V4 illuminate my full-frame camera sensor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The HyperStar 8 has a maximum sensor size of 28mm, and full-frame cameras cannot attach to the HyperStar C8. It suits APS-C and smaller format cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs guiding necessary when imaging with the HyperStar V4 at f\/1.9?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo guiding is required. At f\/1.9 the HyperStar 8 is 25 times faster than the native f\/10 system, so sub-exposures are short and tracking errors matter far less.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat's the difference between the standard adapter and the optional Filter Slider for the HyperStar V4?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe included Standard Camera Adapter holds one 2\" mounted filter inside the adapter. The optional Filter Slider Upgrade replaces this adapter and provides a sliding drawer that allows you to easily swap filters without removing the camera. The slider also includes both M42 and M54 top plates for greater camera compatibility.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I image planets with the Starizona HyperStar V4?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe HyperStar V4 is not designed for planetary imaging. Its short 390mm focal length results in a very small image scale, rendering planets as tiny dots with little detail. For planetary work, you should remove the HyperStar and use the telescope in its native f\/10 configuration (or with a \u003ca href=\"\/en-int\/collections\/barlows-and-extenders\"\u003eBarlow lens\u003c\/a\u003e) to achieve the necessary high magnification.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I balance the HyperStar V4 on my Celestron Evolution 8 fork mount?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eBecause you cannot slide the optical tube on a fork mount, you will need a counterweight. The HyperStar Counterweight (sold separately) is designed for this purpose. It fits into the 1.25\" visual back at the rear of the telescope to offset the weight of the HyperStar and camera on the front.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I achieve sharp focus with the HyperStar V4 at f\/1.9?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003ePrecise focus is critical at f\/1.9. The most reliable method is using a Bahtinov mask, which creates a distinct diffraction pattern that makes it easy to see when you've reached perfect focus. An electronic \u003ca href=\"\/en-int\/collections\/electronic-focusers\"\u003eautofocuser\u003c\/a\u003e controlled by software that measures star FWHM (Full Width at Half Maximum) is also an excellent option for automated and repeatable results.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs it difficult to switch my C8 back to f\/10 after using the HyperStar V4?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. You unthread the HyperStar lens assembly and thread your original secondary mirror back into place. The included Secondary Mirror Holder keeps your secondary safe while it is out of the telescope.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of deep-sky objects can I image with the HyperStar V4 from my backyard?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWith its vast 4.1° field of view, the HyperStar 8 excels at capturing large emission nebulae and star-forming regions. When combined with a dual-band or \u003ca href=\"\/en-int\/collections\/dual-band-filters\"\u003emulti-band filter\u003c\/a\u003e, you can effectively image targets like the North American Nebula (NGC 7000), the Heart and Soul Nebulae (IC 1805 and IC 1848), and the entire Veil Nebula complex, even from light-polluted suburban skies.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the HyperStar V4 require collimation?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the HyperStar V4 has adjustable collimation, so you can fine-tune the alignment of the lens for round stars across the field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eHyperStar 8 (C8 v4)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/1.9\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e390 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eField of View\u003c\/td\u003e\n\u003ctd\u003eUp to 4.1°, coma-free, flat field\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Sensor Size\u003c\/td\u003e\n\u003ctd\u003e28 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescopes\u003c\/td\u003e\n\u003ctd\u003eFastar-compatible Celestron C8 SCT; Celestron EdgeHD 8 with the included EdgeHD Adapter Ring\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Backfocus (included adapter)\u003c\/td\u003e\n\u003ctd\u003e17.5 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIncluded Adapter Threads\u003c\/td\u003e\n\u003ctd\u003eM42 male top (M54 top sold separately)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilters\u003c\/td\u003e\n\u003ctd\u003eOne 2\" (M48) mounted filter in the Standard Camera Adapter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptional Filter Slider Threads\u003c\/td\u003e\n\u003ctd\u003eM42 male and M54 male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLength\u003c\/td\u003e\n\u003ctd\u003e3.5\" (without camera adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDiameter\u003c\/td\u003e\n\u003ctd\u003e3.0\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003eLess than 1 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Coatings\u003c\/td\u003e\n\u003ctd\u003eFully multi-coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFinish\u003c\/td\u003e\n\u003ctd\u003eBlack anodized\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCollimation\u003c\/td\u003e\n\u003ctd\u003eAdjustable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Rotation\u003c\/td\u003e\n\u003ctd\u003eIndependent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCountry of Manufacture\u003c\/td\u003e\n\u003ctd\u003eMade in U.S.A. (Tucson, Arizona)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003eConverts f\/10 to f\/1.9 (prime focus)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003ereplaces the Fastar-compatible secondary mirror assembly\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM42x0.75 (T2) male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eHyperStar 8 (C8 v4) lens\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eEdgeHD Adapter Ring\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eStandard Camera Adapter (M42 male top, 17.5 mm backfocus)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSecondary Mirror Holder\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/starizona-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eStarizona Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Starizona","offers":[{"title":"No Filter Slider","offer_id":49476348543261,"sku":"STZ-HS4-C8","price":1399.0,"currency_code":"CAD","in_stock":true},{"title":"Add Filter Slider","offer_id":68030779457821,"sku":"STZ-HS4-C8-FS","price":1579.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Starizona-HyperStar-8in__38157.1651611969.1280.1280.jpg?v=1684347790"},{"product_id":"starizona-hyperstar-v4-for-celestron-9-25","title":"Starizona HyperStar V4 for Celestron 9.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eConverts Celestron 9.25\" SCTs to an f\/2.2 optical system\u003c\/li\u003e\n\u003cli\u003eReduces focal length to 525mm for wide-field imaging\u003c\/li\u003e\n\u003cli\u003eDelivers a coma-free, flat field of view up to 3° wide\u003c\/li\u003e\n\u003cli\u003eSupports sensors up to 28mm in diagonal\u003c\/li\u003e\n\u003cli\u003eIncludes camera adapter for 17.5mm backfocus\u003c\/li\u003e\n\u003cli\u003eAllows use of one 2\" (M48) mounted filter\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eStarizona HyperStar V4 for Celestron 9.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Starizona HyperStar V4 for Celestron 9.25\" transforms your f\/10 \u003ca href=\"\/en-int\/collections\/schmidt-cassegrain-telescopes\"\u003eSchmidt-Cassegrain\u003c\/a\u003e into an incredibly fast f\/2.2 \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e with a 525mm focal length. By replacing the secondary mirror, this prime-focus corrector lens delivers a massive, coma-free field of view up to 3° wide, for camera sensors up to 28mm diagonal. The faster focal ratio means much shorter exposures, and no guiding and no \u003ca href=\"\/en-int\/collections\/equatorial-wedges\"\u003eequatorial wedge\u003c\/a\u003e are required.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eThe f\/2.2 Prime-Focus Corrector for Celestron 9.25\" SCTs\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar is a multi-element lens assembly that mounts in place of your SCT's secondary mirror, converting the telescope to work at the prime focus of its primary mirror. The result is an imaging system that captures faint details in a fraction of the time required at f\/10.\u003c\/p\u003e\n\u003cp\u003eThis design is intended for deep-sky imagers who want to capture expansive targets like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000) in a single frame. No guiding and no equatorial wedge are required.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e525mm Focal Length at f\/2.2: Unguided Imaging with a 3° Field\u003c\/h3\u003e\n\u003cp\u003eAt f\/2.2, the HyperStar 9.25 gathers light far more rapidly than the telescope's native f\/10 configuration, so each sub-exposure can be a small fraction of the length needed at f\/10.\u003c\/p\u003e\n\u003cp\u003eThe optical system produces a coma-free, flat field that supports sensors up to a 28mm diagonal. This generous field of view, spanning up to 3°, is ideal for framing large emission nebulae and galaxy clusters. Short exposures make tracking errors far less critical.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eNative Compatibility for all 9.25\" Fastar Telescopes (Standard \u0026amp; EdgeHD)\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar 9.25 is engineered for any Celestron C9.25 Schmidt-Cassegrain telescope equipped with a Fastar-compatible, removable secondary mirror. Unlike the HyperStar 8 and 11, which use an EdgeHD Adapter Ring on EdgeHD tubes, the C9.25 version fits both standard SCT and EdgeHD 9.25 optical tubes natively, with no additional adapter required.\u003c\/p\u003e\n\u003cp\u003eThe conversion is reversible: the secondary mirror comes out and the HyperStar lens goes in its place. A protective holder for your secondary mirror is included to keep it safe while you are imaging at f\/2.2.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eCamera Connections: The 17.5mm Backfocus Standard\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar 9.25 includes a Standard Camera Adapter with M42 male T-threads, designed for cameras with a 17.5mm backfocus distance. This covers most popular cooled astrocameras. The fast f\/2.2 focal ratio makes backfocus critical, which is why the adapters are precisely machined.\u003c\/p\u003e\n\u003cp\u003eFor cameras with different backfocus requirements or larger M54 thread sizes, a variety of other adapters are available separately. If you choose the Filter Slider Upgrade, the system includes both M42 and M54 male top plates and is ready for cameras with 17.5mm of backfocus.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFilter Integration: A 2\" Threaded Adapter and Optional Filter Slider\u003c\/h3\u003e\n\u003cp\u003eThe included Standard Camera Adapter accepts one standard 2\" (M48) mounted filter, ideal for a broadband, dual-band or \u003ca href=\"\/en-int\/collections\/uv-ir-clear-and-specialty-filters\"\u003eIR-cut filter\u003c\/a\u003e with a one-shot color camera.\u003c\/p\u003e\n\u003cp\u003eFor imagers using monochrome cameras or who need to switch between filters rapidly, the optional Filter Slider Upgrade is an essential addition. It uses its own HyperStar Filter Slider Adapter in place of the Standard Camera Adapter and lets you swap filters without touching the camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eInstallation \u0026amp; Collimation: Field-Swapping and Independent Camera Rotation\u003c\/h3\u003e\n\u003cp\u003eSwitching between f\/10 and f\/2.2 means exchanging the secondary mirror and the HyperStar lens; the secondary mirror is kept in the included Secondary Mirror Holder while you image.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdjustable Collimation:\u003c\/strong\u003e The HyperStar has collimation adjustment screws, allowing you to fine-tune the optical alignment.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndependent Camera Rotation:\u003c\/strong\u003e Once attached, your camera can be rotated independently of the HyperStar lens. This lets you frame your target without moving the lens.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eBalancing the C9.25: Considerations for GEM and Fork Mounts\u003c\/h3\u003e\n\u003cp\u003eAdding the HyperStar and a camera, weighing approximately 1.8 lb plus the camera's weight, to the front of the optical tube shifts the telescope's center of balance forward. On a \u003ca href=\"\/en-int\/collections\/equatorial-mounts\"\u003eGerman Equatorial Mount\u003c\/a\u003e (GEM), this is easily compensated for by sliding the optical tube forward in its saddle.\u003c\/p\u003e\n\u003cp\u003eFor fork-mounted \u003ca href=\"\/en-int\/collections\/alt-azimuth-mounts\"\u003ealt-azimuth\u003c\/a\u003e telescopes like the Celestron CPC or Evolution series, the optical tube cannot be repositioned. In this case, the HyperStar \u003ca href=\"\/en-int\/collections\/counterweights\"\u003eCounterweight\u003c\/a\u003e (sold separately) fits into the 1.25\" visual back to balance the lens and camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eHyperStar 9.25 vs. 8\/11: Aperture and the f\/2.2 Optical Design\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar 8 and 11 work at f\/1.9, while the HyperStar 9.25 works at f\/2.2.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHyperStar 8 (f\/1.9):\u003c\/strong\u003e The 8\" model is faster with a shorter 390mm focal length, yielding an even wider 4.1° field of view. The C8 has a smaller aperture.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHyperStar 11 (f\/1.9):\u003c\/strong\u003e The 11\" model offers more light-gathering power and a 540mm focal length, and supports larger sensors up to 35mm.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHyperStar 9.25 (f\/2.2):\u003c\/strong\u003e Its 525mm focal length and up to 3° field sit between the HyperStar 8 and 11.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eThe 1.8 lb Anodized Build: Precision from Tucson, Arizona\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar 9.25 weighs approximately 1.8 lb, measures 4.2\" long (without the camera adapter) and 4.1\" in diameter, has a black anodized finish and fully multi-coated optics.\u003c\/p\u003e\n\u003cp\u003eEach HyperStar lens is designed and built by Starizona in Tucson, Arizona.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the Starizona HyperStar 9.25 do to my telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe HyperStar 9.25 is a lens system that replaces your C9.25's secondary mirror, converting it from a slow f\/10 telescope into an incredibly fast f\/2.2 astrograph. This shortens the focal length to 525mm, providing a much wider field of view and allowing you to capture deep-sky images in a fraction of the time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I image without a wedge or guiding with the HyperStar 9.25?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo guiding and no equatorial wedge are required. The f\/2.2 focal ratio allows short exposures, which makes tracking errors far less critical, even on an alt-azimuth mount.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the HyperStar 9.25 handle filters for a color vs. monochrome camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe standard camera adapter included with the HyperStar 9.25 has threads to hold one 2\" (M48) mounted filter, which is ideal for a light pollution or \u003ca href=\"\/en-int\/collections\/dual-band-filters\"\u003edual-band filter\u003c\/a\u003e with a one-shot-color camera. For monochrome imagers who need to switch filters, the optional Filter Slider Upgrade provides a drawer system for quick changes without removing the camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the HyperStar 9.25 difficult to focus?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFocusing is not difficult, but it is more critical than at f\/10. The fast f\/2.2 optics create a very narrow critical focus zone. Using a \u003ca href=\"\/en-int\/collections\/focusing-masks\"\u003eBahtinov mask\u003c\/a\u003e, an electronic \u003ca href=\"\/en-int\/collections\/electronic-focusers\"\u003eautofocuser\u003c\/a\u003e, or focusing software that reports FWHM values is highly recommended for achieving perfect focus.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat cameras work with the included HyperStar 9.25 adapter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe included adapter has standard M42 T-threads and is designed for cameras that have a 17.5mm backfocus. This covers most popular cooled astrocameras. Adapters for other backfocus distances and for DSLRs are available separately.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the HyperStar 9.25 work on my Celestron 9.25 EdgeHD telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The HyperStar 9.25 lens is designed to work natively on both standard C9.25 SCT and EdgeHD 9.25 optical tubes that are Fastar-compatible. No additional adapters are needed to switch between the two telescope versions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I balance my CPC 925 fork-mounted telescope with the HyperStar 9.25 attached?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eBecause you cannot slide the optical tube on a fork mount, you will need a counterweight. The HyperStar Counterweight (sold separately) fits into the 1.25\" visual back on the rear of the telescope to balance the HyperStar and your camera. The Celestron CPC is among the fork mounts where it is commonly used.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I still use my C9.25 at f\/10 after installing the HyperStar 9.25?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. Unthread the HyperStar lens and put your secondary mirror back in place. The included Secondary Mirror Holder keeps the secondary safe while the HyperStar is in use.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of field of view can I expect from the HyperStar 9.25 when imaging the Andromeda Galaxy (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWith a field of view of up to 3 degrees, the HyperStar 9.25 can easily frame the entire Andromeda Galaxy (M31) in a single frame with a sensor up to 28mm in diagonal, which the native f\/10 focal length cannot do.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is the HyperStar 9.25 f\/2.2 when other models are f\/1.9?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe HyperStar 9.25 works at f\/2.2 while the HyperStar 8 and 11 work at f\/1.9. The 9.25 still gives a very large speed increase over the native f\/10.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need to collimate the HyperStar 9.25 lens?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the HyperStar lens has adjustable collimation, which lets you fine-tune its alignment for round stars across the field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the HyperStar 9.25 compatible with full-frame sensors?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The HyperStar 9.25 produces a fully illuminated and corrected image circle for sensors with a diagonal up to 28mm. It suits APS-C and smaller format sensors; a full-frame sensor (about 43mm diagonal) is larger than that.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eHyperStar 9.25 (C9.25 v4)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/2.2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e525 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eField of View\u003c\/td\u003e\n\u003ctd\u003eUp to 3°, coma-free, flat field\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Sensor Size\u003c\/td\u003e\n\u003ctd\u003e28 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescopes\u003c\/td\u003e\n\u003ctd\u003eAny Celestron C9.25 with Fastar secondary mirror, standard or EdgeHD 9.25 (no additional adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Backfocus (included adapter)\u003c\/td\u003e\n\u003ctd\u003e17.5 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIncluded Adapter Threads\u003c\/td\u003e\n\u003ctd\u003eM42 male top (M54 top sold separately)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilters\u003c\/td\u003e\n\u003ctd\u003eOne 2\" (M48) mounted filter in the Standard Camera Adapter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptional Filter Slider Threads\u003c\/td\u003e\n\u003ctd\u003eM42 male and M54 male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLength\u003c\/td\u003e\n\u003ctd\u003e4.2\" (without camera adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDiameter\u003c\/td\u003e\n\u003ctd\u003e4.1\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003eApprox. 1.8 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Coatings\u003c\/td\u003e\n\u003ctd\u003eFully multi-coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFinish\u003c\/td\u003e\n\u003ctd\u003eBlack anodized\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCollimation\u003c\/td\u003e\n\u003ctd\u003eAdjustable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Rotation\u003c\/td\u003e\n\u003ctd\u003eIndependent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCountry of Manufacture\u003c\/td\u003e\n\u003ctd\u003eMade in U.S.A. (Tucson, Arizona)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003eConverts f\/10 to f\/2.2 (prime focus)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003ereplaces the Fastar-compatible secondary mirror assembly\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM42x0.75 (T2) male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eHyperStar 9.25 (C9.25 v4) lens\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eStandard Camera Adapter, M42 male top, 17.5 mm backfocus (No Filter Slider version)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSecondary Mirror Holder\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eFilter Slider Upgrade (Add Filter Slider version): Filter Slider, M42 male plate with dust cap, M48 female plate, M54 male plate with dust cap, HyperStar Filter Slider Adapter for 17.5 mm backfocus cameras\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/starizona-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eStarizona Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Starizona","offers":[{"title":"No Filter Slider","offer_id":44968007663901,"sku":"STZ-HS4-C925","price":1679.0,"currency_code":"CAD","in_stock":true},{"title":"Add Filter Slider","offer_id":44968007696669,"sku":"STZ-HS4-C925-FS","price":1859.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Starizona-Hyperstar-Celestron-9-25__40693.1653511350.1280.1280.jpg?v=1684347781"},{"product_id":"askar-0-7x-universal-reducer-for-107phq-130phq-151phq","title":"Askar 0.7x Universal Reducer for 107PHQ\/130PHQ\/151PHQ","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e0.7x Focal Reduction Factor\u003c\/li\u003e\n\u003cli\u003e44mm Full-Frame Image Circle\u003c\/li\u003e\n\u003cli\u003eMaintains a Standard 55mm Backfocus\u003c\/li\u003e\n\u003cli\u003e3-Element Air-Spaced Design with ED Glass\u003c\/li\u003e\n\u003cli\u003eOptimized for Askar 107PHQ, 130PHQ, and 151PHQ Telescopes\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 0.7x Universal Reducer for 107PHQ\/130PHQ\/151PHQ\u003c\/h2\u003e\n\u003cp\u003eThe Askar 3” 0.7x Full-Frame Reducer transforms the \u003ca href=\"\/en-int\/products\/askar-107phq-f-7-quadruplet-apo\"\u003e107PHQ\u003c\/a\u003e, \u003ca href=\"\/en-int\/products\/askar-130phq-f-7-quadruplet-apo\"\u003e130PHQ\u003c\/a\u003e, and \u003ca href=\"\/en-int\/products\/askar-151phq\"\u003e151PHQ\u003c\/a\u003e \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrographs\u003c\/a\u003e into faster, wider-field instruments perfect for deep-sky imaging. Its 3-element optical design incorporates ED glass to deliver a corrected 44mm image circle, while maintaining the industry-standard 55mm backfocus for easy integration with your existing camera and \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheel\u003c\/a\u003e setup. This reducer effectively shortens exposure times by increasing the light-gathering power of your f\/7 107PHQ or 151PHQ to a rapid f\/4.9 (f\/5.4 on the f\/7.7 130PHQ).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFaster Imaging at f\/4.9: A 0.7x Triplet ED Reducer\u003c\/h3\u003e\n\u003cp\u003eBy reducing the native f\/7 focal ratio of the 107PHQ and 151PHQ to f\/4.9 (f\/7.7 to f\/5.4 on the 130PHQ), this 0.7x reducer cuts required exposure times nearly in half. This allows you to gather more signal on faint targets in less time, maximizing your productivity during short imaging windows. The air-spaced triplet optical design, which includes one element of extra-low dispersion (ED) glass, ensures sharp, high-contrast images with excellent color correction across the field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFull-Frame Coverage: A Corrected 44mm Image Circle\u003c\/h3\u003e\n\u003cp\u003eEngineered specifically for large-format sensors, this reducer illuminates a 44mm image circle. This is large enough to cover full-frame (36x24mm) CMOS and CCD sensors without vignetting, ensuring your entire frame is evenly lit from corner to corner. You can capture vast nebulae like the Veil Nebula complex or the Andromeda Galaxy (M31) in their entirety, without sacrificing image brightness or star quality at the edges of your frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eSeamless Integration: 55mm Backfocus and Multi-Thread Adapters\u003c\/h3\u003e\n\u003cp\u003eAskar designed this reducer for straightforward integration into any standard imaging train. It provides a precise 55mm backfocus, the common standard for DSLRs, mirrorless cameras, and dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e with a filter wheel. The reducer includes M68, M54, and M48 thread adapters, giving you the flexibility to connect to virtually any \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e, \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guider\u003c\/a\u003e, or camera system without needing to source additional parts.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the Askar 0.7x reducer do to the focal length of the Askar 130PHQ?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar 130PHQ has a native focal length of 1000mm at f\/7.7. The \u003cstrong\u003e0.7x reducer\u003c\/strong\u003e will shorten its focal length to 700mm and change the focal ratio to a much faster f\/5.4, allowing for wider fields of view and significantly shorter exposure times.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Askar 0.7x reducer compatible with full-frame cameras?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. It is designed to produce a corrected \u003cstrong\u003e44mm image circle\u003c\/strong\u003e, which is large enough to fully illuminate a standard full-frame sensor (36x24mm) without significant vignetting, providing sharp stars across the entire frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect my camera to the Askar 0.7x Universal Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer is designed for a standard \u003cstrong\u003e55mm backfocus\u003c\/strong\u003e from its rearmost flange. It includes M68, M54, and M48 adapters, allowing you to directly connect most dedicated astronomy cameras, DSLRs (with an M48 \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e), and filter wheels using common extension tubes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this reducer introduce chromatic aberration to my Askar 107PHQ?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The reducer features a \u003cstrong\u003e3-element optical design that includes one ED (Extra-low Dispersion) glass element\u003c\/strong\u003e. This design actively corrects for chromatic aberration, ensuring that the excellent color fidelity of the 107PHQ's quadruplet objective is maintained.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Askar 0.7x reducer help when imaging large targets like the North American Nebula (NGC 7000)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eOn a telescope like the Askar 151PHQ (1057mm focal length), the native field of view is too narrow to frame the entire North American Nebula. By reducing the focal length to approximately 740mm, the \u003cstrong\u003e0.7x reducer\u003c\/strong\u003e expands the field of view, allowing you to capture the entire nebula and the adjacent Pelican Nebula (IC 5070) in a single shot with a full-frame camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Askar 0.7x reducer for visual observing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis accessory is designed and optically corrected specifically for astrophotography. While you might be able to reach focus with some long-focal-length \u003ca href=\"\/en-int\/collections\/eyepieces\"\u003eeyepieces\u003c\/a\u003e, it is not optimized for visual use and will likely result in suboptimal views. Its primary purpose is to create a flat, corrected field for a camera sensor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.7x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescopes\u003c\/td\u003e\n\u003ctd\u003eAskar 107PHQ, 130PHQ, 151PHQ\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e3-element air-spaced triplet with one ED element\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBackfocus\u003c\/td\u003e\n\u003ctd\u003e55mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConnection to Focuser\u003c\/td\u003e\n\u003ctd\u003e3-inch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutput Thread Adapters\u003c\/td\u003e\n\u003ctd\u003eM68x1, M54x0.75, M48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum Diameter\u003c\/td\u003e\n\u003ctd\u003e80mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eKind\u003c\/td\u003e\n\u003ctd\u003eReducer (full frame)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003e3\" barrel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e0.7x reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eM68 adapter\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eM54 adapter\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eM48 adapter\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_2025_First_Half_Product_Collection_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":44968036466973,"sku":"ASK-ASF107130RE","price":538.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Askar-PHQ-Reducer__94249.1657565838.1280.1280.jpg?v=1684348170"},{"product_id":"askar-0-76x-reducer-for-80phq","title":"Askar 0.76x Reducer for 80PHQ","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e0.76x reduction factor specifically for the Askar 80PHQ\u003c\/li\u003e\n\u003cli\u003eReduces focal ratio from f\/7.5 to a faster f\/5.7\u003c\/li\u003e\n\u003cli\u003eCreates a new focal length of 456mm\u003c\/li\u003e\n\u003cli\u003eGenerates a 44mm image circle, fully illuminating full-frame sensors\u003c\/li\u003e\n\u003cli\u003eMaintains a standard 55mm backfocus for easy camera connection\u003c\/li\u003e\n\u003cli\u003eFeatures an integrated M48x0.75 filter thread\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 0.76x Reducer for 80PHQ\u003c\/h2\u003e\n\u003cp\u003eThis Askar 0.76x Reducer is engineered specifically for the \u003ca href=\"\/en-int\/products\/askar-80phq-f-7-quadruplet-apo\"\u003e80PHQ\u003c\/a\u003e \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e, transforming its native f\/7.5 optics into a faster f\/5.7 imaging system with a 456mm focal length. The 3-element air-spaced triplet design delivers a corrected 44mm image circle, fully illuminating full-frame sensors while maintaining a standard 55mm backfocus for straightforward integration with your camera and \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheel\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA Triplet Design for f\/5.7 Speed and a 456mm Focal Length\u003c\/h3\u003e\n\u003cp\u003eBy decreasing the focal ratio of the 80PHQ from f\/7.5 to f\/5.7, this 0.76x reducer shortens required exposure times by approximately 42%, allowing you to capture more signal in less time. The resulting 456mm focal length provides a wider field of view, ideal for framing large nebulae and star clusters. The internal 3-element triplet lens configuration ensures that the wider field remains sharp and well-corrected across the frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFull-Frame Imaging: 44mm Image Circle and Standard 55mm Backfocus\u003c\/h3\u003e\n\u003cp\u003eThe reducer is designed to produce a 44mm image circle, providing full, unvignetted illumination for cameras with full-frame (36x24mm) sensors. It connects directly to the 80PHQ's \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e and features a standard 55mm backfocus, simplifying the process of attaching a DSLR, mirrorless, or dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy camera\u003c\/a\u003e with the correct spacing. An integrated M48x0.75 (2-inch) filter thread allows you to easily add light pollution or \u003ca href=\"\/en-int\/collections\/narrowband-filters\"\u003enarrowband filters\u003c\/a\u003e into your imaging train without needing a separate \u003ca href=\"\/en-int\/collections\/filter-wheels-and-drawers\"\u003efilter drawer\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the Askar 0.76x Reducer do for my 80PHQ telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar 0.76x Reducer converts your Askar 80PHQ from its native f\/7.5 focal ratio to a faster f\/5.7. This shortens your exposure times and provides a wider field of view with a new focal length of 456mm, making it better suited for capturing large deep-sky objects.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 44mm image circle of this reducer large enough for my full-frame camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The 44mm image circle is specifically designed to be larger than the diagonal of a standard full-frame sensor (which is approximately 43.3mm). This ensures your full-frame camera sensor is fully illuminated without vignetting caused by the reducer.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect my camera to the Askar 0.76x Reducer for the 80PHQ?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer provides a standard 55mm backfocus from its rearmost thread. This is the standard spacing for most \u003ca href=\"\/en-int\/collections\/deep-sky-cameras\"\u003ecooled astronomy cameras\u003c\/a\u003e when used with a filter wheel, or for a DSLR\/mirrorless camera with its corresponding M48 T-ring. You simply add the necessary M48 spacers to achieve the 55mm distance to your camera's sensor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the f\/5.7 speed help when imaging the Andromeda Galaxy (M31) with the 80PHQ?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Andromeda Galaxy (M31) is a very large target that benefits from the wider 456mm focal length. More importantly, the faster f\/5.7 optics gather light more quickly than the native f\/7.5, allowing you to capture the faint outer arms and dust lanes of the galaxy with shorter individual exposures, improving your overall signal-to-noise ratio in a single imaging session.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use filters with the Askar 0.76x reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer has a built-in M48x0.75 (2-inch) filter thread on the camera side, allowing you to easily screw in standard 2-inch mounted filters for light pollution reduction or narrowband imaging.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this 0.76x reducer work on telescopes other than the Askar 80PHQ?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this reducer is specifically designed and optically matched to work with the Askar 80PHQ astrograph. Using it on other telescopes will likely result in poor optical correction, field curvature, and an inability to reach focus.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReducer Type\u003c\/td\u003e\n\u003ctd\u003e0.76x Focal Reducer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescope\u003c\/td\u003e\n\u003ctd\u003eAskar 80PHQ\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResulting Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/5.7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResulting Focal Length\u003c\/td\u003e\n\u003ctd\u003e456mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e3-element, air-spaced triplet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thread\u003c\/td\u003e\n\u003ctd\u003eM48x0.75 (2-inch)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Outer Diameter\u003c\/td\u003e\n\u003ctd\u003e68mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM48x0.75 (2\" filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 0.76x Reducer for 80PHQ\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software \u0026amp; Drivers\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":44968076083485,"sku":"ASK-ASKAR80R","price":368.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Askar-80PHQ-Reducer__01912.1679584601.1280.1280.jpg?v=1684348743"},{"product_id":"askar-1x-field-flattener-for-103apo","title":"Askar 1x Field Flattener for 103APO","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eCorrects field curvature and coma for the Askar 103APO\u003c\/li\u003e\n\u003cli\u003eMaintains the native 700.4mm focal length and f\/6.8 ratio\u003c\/li\u003e\n\u003cli\u003eTriplet optical design delivers sharp stars edge-to-edge\u003c\/li\u003e\n\u003cli\u003eProvides a 44mm full-frame corrected image circle\u003c\/li\u003e\n\u003cli\u003eStandard 55mm back focus from the M48 thread\u003c\/li\u003e\n\u003cli\u003eIncludes M54 and M48 camera adapters and a 2\" filter thread\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 1x Field Flattener for 103APO\u003c\/h2\u003e\n\u003cp\u003eThe Askar 1x Field Flattener is engineered specifically for the \u003ca href=\"\/en-int\/products\/askar-103apo-f-6-8-triplet\"\u003e103APO\u003c\/a\u003e \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractor\u003c\/a\u003e, correcting field curvature across a 44mm full-frame image circle while maintaining the telescope's native 700.4mm focal length and f\/6.8 focal ratio. This 0.58kg flattener utilizes a triplet optical design to deliver sharp stars to the edge of the frame and integrates into any standard imaging train with 55mm of back focus from its M48 male thread.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 44mm Flat Field for the Askar 103APO\u003c\/h3\u003e\n\u003cp\u003eThis flattener's primary function is to eliminate the field curvature and coma inherent in a refracting telescope, ensuring star points remain perfectly round across the entire sensor. The triplet air-spaced lens design achieves this correction over a 44mm image circle, making it an essential accessory for imagers using full-frame DSLR, mirrorless, or dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e with the Askar 103APO.\u003c\/p\u003e\n\u003cp\u003eBy using a 1x magnification factor, the flattener preserves the telescope's native 700.4mm focal length and f\/6.8 focal ratio. This allows you to capture wide-field targets with the maximum resolution and light-gathering power the 103APO optics can provide, but with the critical addition of a perfectly flat field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e55mm Back Focus and Standardized Connections\u003c\/h3\u003e\n\u003cp\u003eAskar designed this flattener for seamless integration into modern imaging setups. It provides the industry-standard 55mm of back focus measured from the base of its male M48x0.75 thread, which simplifies connecting most cameras and \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e without complex calculations. Simply add your camera's \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e or standard spacers to reach the 55mm distance for optimal performance.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eVersatile Adapters:\u003c\/strong\u003e The camera side includes both M54×0.75 and M48×0.75 threaded adapters, providing direct attachment for a wide range of cameras, \u003ca href=\"\/en-int\/collections\/filter-wheels-and-drawers\"\u003efilter drawers\u003c\/a\u003e, and \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntegrated Filter Cell:\u003c\/strong\u003e A built-in M48x0.75 thread inside the adapter acts as a 2-inch filter cell, allowing you to mount light pollution or \u003ca href=\"\/en-int\/collections\/narrowband-filters\"\u003enarrowband filters\u003c\/a\u003e directly within the flattener itself.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRobust Build:\u003c\/strong\u003e The entire housing is CNC-machined for precise optical alignment and weighs a solid 0.58kg, ensuring no flexure in the imaging train.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main purpose of the Askar 1x Flattener for the 103APO?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar 1x Flattener is designed to correct optical aberrations like \u003cstrong\u003efield curvature\u003c\/strong\u003e and \u003cstrong\u003ecoma\u003c\/strong\u003e in the Askar 103APO telescope. This ensures that stars are sharp and point-like across the entire imaging sensor, which is crucial for astrophotography, especially with large-format cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Askar 1x Flattener change the 103APO's focal length?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. As a \u003cstrong\u003e1x flattener\u003c\/strong\u003e, it does not reduce or extend the focal length. When attached to the Askar 103APO, the telescope maintains its native \u003cstrong\u003e700.4mm focal length\u003c\/strong\u003e and \u003cstrong\u003ef\/6.8 focal ratio\u003c\/strong\u003e, simply delivering a corrected, flat field of view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat cameras are compatible with the Askar 1x Flattener's 55mm back focus?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe standard \u003cstrong\u003e55mm back focus\u003c\/strong\u003e is compatible with most imaging systems. This includes:\n\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eDSLR and mirrorless cameras with a standard T-ring adapter.\u003c\/li\u003e\n\u003cli\u003eDedicated astronomy cameras when combined with the appropriate spacers to achieve the 55mm distance.\u003c\/li\u003e\n\u003c\/ul\u003e\nThe flattener includes both M54 and M48 threads to connect to a wide variety of accessories.\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2-inch filters with the Askar 1x Flattener for the 103APO?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The Askar 1x Flattener has a built-in \u003cstrong\u003eM48x0.75 filter thread\u003c\/strong\u003e on the camera side. This allows you to directly screw in standard 2-inch astronomy filters for light pollution suppression or narrowband imaging.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Askar 1x Flattener improve images of the Andromeda Galaxy (M31) with the 103APO?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA large target like the Andromeda Galaxy (M31) will stretch across the entire field of a full-frame sensor when imaged with the Askar 103APO. Without this flattener, stars at the edges of the galaxy would appear elongated or out of focus. The \u003cstrong\u003eAskar 1x Flattener\u003c\/strong\u003e ensures that the outer spiral arms and surrounding star fields of M31 are just as sharp as the galactic core.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Askar 1x Flattener fully illuminate my full-frame sensor on an f\/6.8 system?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The flattener is specifically designed to produce a corrected and illuminated \u003cstrong\u003e44mm image circle\u003c\/strong\u003e. This is large enough to cover a standard full-frame sensor (which has a 43.3mm diagonal) without vignetting, making it a perfect match for the Askar 103APO's f\/6.8 optics.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e3-Element Air-Spaced (Triplet)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification\u003c\/td\u003e\n\u003ctd\u003e1x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescope\u003c\/td\u003e\n\u003ctd\u003eAskar 103APO\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length with 103APO\u003c\/td\u003e\n\u003ctd\u003e700.4mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio with 103APO\u003c\/td\u003e\n\u003ctd\u003ef\/6.8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCorrected Image Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (from M48x0.75 male thread base)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Threads\u003c\/td\u003e\n\u003ctd\u003eM54x0.75 \u0026amp; M48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInternal Filter Threads\u003c\/td\u003e\n\u003ctd\u003eM48x0.75 (2-inch)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.58 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eM84x1 Male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM54x0.75 male, M48x0.75 (2\" filter) male, M48x0.75 (2\" filter) female\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 1x Field Flattener for 103APO\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_103APO_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":46861263405341,"sku":"ASK-ASKFL10310","price":307.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-103APO-Field-Flattener-ASKFL10310-1.png?v=1697487604"},{"product_id":"askar-0-8x-reducer-for-103apo","title":"Askar 0.8x Reducer for 103APO","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces telescope focal ratio to a faster f\/5.44\u003c\/li\u003e\n\u003cli\u003eShortens 103APO focal length to 560.32mm for wider fields\u003c\/li\u003e\n\u003cli\u003eTriplet optical design provides field flattening\u003c\/li\u003e\n\u003cli\u003eStandard 55mm back focus for easy camera connection\u003c\/li\u003e\n\u003cli\u003eIntegrated M48x0.75 threads for 2\" filters\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 0.8x Reducer for 103APO\u003c\/h2\u003e\n\u003cp\u003eThe Askar 0.8x Reducer is engineered specifically for the \u003ca href=\"\/en-int\/products\/askar-103apo-f-6-8-triplet\"\u003eAskar 103APO\u003c\/a\u003e, transforming it into a faster f\/5.44 imaging system and shortening its focal length to 560.32mm for wider fields of view. This triplet reducer maintains a standard 55mm back focus from its M48 thread and weighs just 0.48kg, adding minimal load to the \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e while significantly increasing light-gathering speed.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eTriplet Optics: A Faster f\/5.44 System for the 103APO\u003c\/h3\u003e\n\u003cp\u003eBy reducing the 103APO's native focal ratio to f\/5.44, this corrector significantly cuts down required exposure times, allowing you to capture more signal on faint targets in a single session. The triplet optical design also acts as a \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003efield flattener\u003c\/a\u003e, ensuring sharp, point-like stars across a full-frame sensor, which is critical when imaging expansive targets like the North American Nebula (NGC 7000) or the Heart and Soul Nebulae (IC 1805 and IC 1848).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eMechanical Connectivity: 55mm Back Focus for Standardized Imaging Trains\u003c\/h3\u003e\n\u003cp\u003eThis reducer is designed for straightforward integration into your existing setup. It provides the industry-standard 55mm of back focus from the base of its M48 male thread, simplifying the connection of DSLRs (with a standard \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e) and dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e with \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e and \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e. The rear of the reducer includes both M54×0.75 and M48×0.75 adapters, and a built-in M48×0.75 thread allows for direct installation of 2-inch filters without adding extra spacing components.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the Askar 0.8x Reducer do for my 103APO telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar 0.8x Reducer shortens the focal length of your 103APO to \u003cstrong\u003e560.32mm\u003c\/strong\u003e and increases its speed to \u003cstrong\u003ef\/5.44\u003c\/strong\u003e. This provides a wider field of view, allowing you to fit larger celestial objects into your frame, and reduces exposure times, enabling you to collect data on faint nebulae and galaxies more efficiently.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect my camera to the Askar 103APO 0.8x Reducer to achieve the correct 55mm back focus?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer provides \u003cstrong\u003e55mm of back focus\u003c\/strong\u003e from the base of the included M48 male adapter thread. To achieve this spacing, you simply add extension tubes or accessories between the reducer and your camera sensor until the total distance is 55mm. A typical DSLR with a T-ring already has approximately 55mm of spacing, making the connection direct.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2-inch filters with the Askar 103APO 0.8x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer features an integrated \u003cstrong\u003eM48x0.75 female thread\u003c\/strong\u003e on the camera side, which is the standard for 2-inch astronomy filters. You can thread your filters directly into the reducer for light pollution suppression or narrowband imaging.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Askar 103APO 0.8x Reducer suitable for planetary imaging?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile technically usable, a reducer is not ideal for planetary imaging. Reducers decrease focal length to capture wider fields, which is the opposite of the high magnification needed to resolve detail on planets like Jupiter and Saturn. For planetary work, you should use the Askar 103APO at its native focal length or with a \u003ca href=\"\/en-int\/collections\/barlows-and-extenders\"\u003eBarlow lens\u003c\/a\u003e to increase magnification.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Askar 103APO 0.8x Reducer improve imaging of large targets like the Andromeda Galaxy (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAt its native focal length, the Askar 103APO may be too narrow to frame the entire Andromeda Galaxy (M31) and its satellite galaxies with a larger sensor. By reducing the focal length to \u003cstrong\u003e560.32mm\u003c\/strong\u003e, the reducer widens the field of view, allowing you to capture the full galactic structure in a single frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this reducer provide a flat field for my full-frame DSLR or CMOS camera on the Askar 103APO?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the \u003cstrong\u003etriplet\u003c\/strong\u003e optical design of the Askar 0.8x Reducer is engineered to provide field flattening that illuminates a full-frame sensor. This ensures that stars remain sharp and round from the center of your image all the way to the corners, which is essential for creating high-quality astrophotographs.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.8x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFinal Focal Length (on 103APO)\u003c\/td\u003e\n\u003ctd\u003e560.32mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFinal Focal Ratio (on 103APO)\u003c\/td\u003e\n\u003ctd\u003ef\/5.44\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eTriplet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (from M48 thread base)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.48 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear-End Threads\u003c\/td\u003e\n\u003ctd\u003eM54×0.75, with M48×0.75 adapter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Threads\u003c\/td\u003e\n\u003ctd\u003eM48×0.75 (for 2\" filters)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e44 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eM84x1 Male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned For\u003c\/td\u003e\n\u003ctd\u003eAskar 103APO\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 0.8x Reducer for 103APO\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_103APO_0.8x_Reducer_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":46861341458717,"sku":"ASK-ASKRE10308","price":307.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-103APO-0-8x-Reducer-ASKRE10308-1.png?v=1697488015"},{"product_id":"askar-0-6x-reducer-for-103apo","title":"Askar 0.6x Reducer for 103APO","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eTransforms Askar 103APO to an f\/4.08, 420.24mm focal length system\u003c\/li\u003e\n\u003cli\u003eQuadruplet optical design provides field flattening for full-frame sensors\u003c\/li\u003e\n\u003cli\u003eStandard 55mm back focus for easy camera and accessory integration\u003c\/li\u003e\n\u003cli\u003eIncludes M68, M54, and M48 adapters for versatile camera connection\u003c\/li\u003e\n\u003cli\u003eIntegrated M48x0.75 thread for use with 2\" filters\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 0.6x Reducer for 103APO\u003c\/h2\u003e\n\u003cp\u003eThe Askar 0.6x Reducer for \u003ca href=\"\/en-int\/products\/askar-103apo-f-6-8-triplet\"\u003e103APO\u003c\/a\u003e transforms the telescope into a fast f\/4.08 \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e, shortening the focal length to 420.24mm for capturing vast celestial targets. This dedicated quadruplet reducer is optically matched to the 103APO, delivering a flat field and maintaining sharp stars from edge to edge while adhering to a standard 55mm back focus distance for your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eTransforming the 103APO to an f\/4.08 Astrograph\u003c\/h3\u003e\n\u003cp\u003eBy reducing the native focal ratio to f\/4.08, this accessory dramatically cuts required exposure times, allowing you to gather more signal in less time. The quadruplet optical design not only reduces the focal length but also acts as a \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003efield flattener\u003c\/a\u003e, correcting for optical aberrations and ensuring pinpoint stars across a wide, flat image circle suitable for full-frame cameras. At a focal length of 420.24mm, you can frame large emission nebulae like the North American Nebula (NGC 7000) or the entire Andromeda Galaxy (M31) with ease.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA Detachable-Tube Design for f\/4 Speed\u003c\/h3\u003e\n\u003cp\u003eAchieving this faster focal ratio requires a unique mechanical integration with the Askar 103APO. To use the 0.6x reducer, you must detach the rear section of the main telescope tube, effectively shortening the instrument to achieve focus. This purpose-built design ensures perfect spacing and optical alignment. The reducer itself adds 0.98kg to your imaging setup, a factor to consider when balancing your mount for precise tracking.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e55mm Back Focus with M48, M54, and M68 Adapters\u003c\/h3\u003e\n\u003cp\u003eThe Askar 0.6x Reducer simplifies camera connection by using the industry-standard 55mm back focus distance from the base of its M48 male thread. This compatibility works seamlessly with most DSLRs (with a standard \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e) and dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e. For maximum flexibility, the reducer includes a set of adapters for M68×1, M54×0.75, and M48×0.75 threads, ensuring you can connect a wide variety of cameras, \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e, and \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guiders\u003c\/a\u003e. The M48 adapter also features an internal thread for mounting 2-inch filters directly.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 0.6x reducer change the Askar 103APO's imaging characteristics?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt transforms the Askar 103APO into a faster, wider-field instrument. The focal ratio is reduced to \u003cstrong\u003ef\/4.08\u003c\/strong\u003e and the focal length to \u003cstrong\u003e420.24mm\u003c\/strong\u003e. This allows for significantly shorter exposure times and the ability to frame much larger deep-sky objects in a single shot.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need to modify my Askar 103APO to use this 0.6x reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The Askar 103APO features a detachable tube design specifically for this reducer. You must remove the rear section of the optical tube to shorten the telescope, which allows the reducer to reach focus and function correctly. This is a required step for proper installation.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the correct back focus for the Askar 103APO 0.6x reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe required back focus is a standard \u003cstrong\u003e55mm\u003c\/strong\u003e. This distance is measured from the base of the M48 male thread on the reducer to your camera's sensor. Most dedicated astronomy cameras and DSLR\/mirrorless cameras with T-rings are designed around this standard distance.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2\" filters with the Askar 103APO 0.6x reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The included M48 adapter has an internal \u003cstrong\u003eM48×0.75 thread\u003c\/strong\u003e, which allows you to screw in standard 2-inch astronomy filters directly. This is ideal for adding light pollution or \u003ca href=\"\/en-int\/collections\/narrowband-filters\"\u003enarrowband filters\u003c\/a\u003e to your imaging train without needing a separate \u003ca href=\"\/en-int\/collections\/filter-wheels-and-drawers\"\u003efilter drawer\u003c\/a\u003e or wheel.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Askar 103APO 0.6x reducer help when imaging the North American Nebula (NGC 7000)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe North American Nebula is a very large target, spanning several degrees of the sky. The reducer's \u003cstrong\u003e420.24mm\u003c\/strong\u003e focal length provides a much wider field of view than the native 103APO, allowing you to capture the entire nebula and the adjacent Pelican Nebula (IC 5070) in a single frame with most full-frame or APS-C sensors.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the f\/4.08 speed from this Askar reducer beneficial for imaging broadband targets like the Andromeda Galaxy (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. The fast \u003cstrong\u003ef\/4.08\u003c\/strong\u003e focal ratio gathers light much more quickly than the native telescope. When imaging a broadband target like M31, this means you can capture faint outer dust lanes and details with shorter individual sub-exposures, improving your signal-to-noise ratio and reducing the impact of tracking errors or changing sky conditions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eQuadruplet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.6x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Length (103APO)\u003c\/td\u003e\n\u003ctd\u003e420.24mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Ratio (103APO)\u003c\/td\u003e\n\u003ctd\u003ef\/4.08\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (from base of M48 thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection Threads\u003c\/td\u003e\n\u003ctd\u003eM68×1, M54×0.75, M48×0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thread\u003c\/td\u003e\n\u003ctd\u003eM48×0.75 (internal)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.98kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e44 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eM84x1 Male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned For\u003c\/td\u003e\n\u003ctd\u003eAskar 103APO\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 0.6x Reducer for 103APO\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_103APO_0.6x_Reducer_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":46861375701277,"sku":"ASK-ASKRE10306","price":461.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-103APO-0-6x-Reducer-ASKRE10306-1.png?v=1697488274"},{"product_id":"starizona-sct-corrector-lf-large-format-reducer-coma-corrector","title":"Starizona SCT Corrector LF - Large Format Reducer\/Coma Corrector","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocal Reducer:\u003c\/strong\u003e 0.7x, f\/7 on a C11 and f\/7.2 on a C14\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eComa Corrector:\u003c\/strong\u003e Corrects inherent off-axis coma in standard SCTs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImage Circle:\u003c\/strong\u003e 42mm, designed for full-frame (35mm format) sensors\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Celestron C11 and C14 standard SCTs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting Thread:\u003c\/strong\u003e 3.29\"-16 tpi for direct attachment to the rear cell\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBackfocus:\u003c\/strong\u003e 146mm from mounting threads for complex imaging trains\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 730 g (1.6 lb)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eStarizona SCT Corrector LF - Large Format Reducer\/Coma Corrector\u003c\/h2\u003e\n\u003cp\u003eThe Starizona SCT Corrector LF transforms your Celestron C11 or C14 into a faster, coma-corrected \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e with its 0.7x reduction factor. It delivers a 42mm full-frame image circle, reducing a C11 to f\/7 at 1960mm and a C14 to f\/7.2 at 2560mm. The generous 146mm of backfocus provides ample room for complex imaging trains, all while correcting the native coma of standard SCTs for sharp stars across the field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 0.7x Reducer and Coma Corrector for Full-Frame Sensors\u003c\/h3\u003e\n\u003cp\u003eStandard \u003ca href=\"\/en-int\/collections\/schmidt-cassegrain-telescopes\"\u003eSchmidt-Cassegrain telescopes\u003c\/a\u003e are powerful instruments, but their native f\/10 focal ratio and off-axis coma present challenges for astrophotography. The Starizona SCT Corrector LF solves both problems by simultaneously reducing the focal ratio by a factor of 0.7x and correcting for coma, resulting in sharper stars and significantly shorter exposure times.\u003c\/p\u003e\n\u003cp\u003eThis Large Format (LF) version is specifically engineered for imagers using full-frame sensors, such as those found in 35mm-format DSLRs and large-chip dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e. By correcting the field across a wide 42mm diagonal, it enables you to capture expansive deep-sky objects without the distorted, elongated stars that plague uncorrected SCTs.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eDesigned for Celestron C11 \u0026amp; C14 3.29\" Rear Threads\u003c\/h3\u003e\n\u003cp\u003eThe SCT Corrector LF is optimized for Celestron's largest standard SCTs: the C11 and C14. Unlike smaller correctors that use a 2-inch barrel, this unit threads directly onto the large 3.29\"-16 tpi rear cell of these telescopes.\u003c\/p\u003e\n\u003cp\u003eStarizona designs it for the standard (non-EdgeHD) Celestron C11 and C14; for smaller SCTs it offers the SCT Corrector IV.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eOptical Conversion: f\/7 on a C11, f\/7.2 on a C14\u003c\/h3\u003e\n\u003cp\u003eBy reducing the native focal ratio (f\/10 on the C11, f\/11 on the C14), the SCT Corrector LF dramatically shortens required exposure times. The faster optical system allows you to gather more signal in less time, improving your signal-to-noise ratio and making it easier to capture faint details in galaxies and nebulae.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOn a C11:\u003c\/strong\u003e The focal ratio becomes f\/7, and the focal length is reduced to 1960mm.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOn a C14:\u003c\/strong\u003e The focal ratio becomes f\/7.2, and the focal length is reduced to 2560mm.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThis wider field of view is ideal for framing larger targets that would not fit in the native field of an SCT. The combination of a wider, faster system makes the C11 and C14 significantly more capable deep-sky imaging platforms.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 42mm Image Circle for 35mm Format Sensors\u003c\/h3\u003e\n\u003cp\u003eThe primary advantage of the LF model is its 42mm corrected image circle, designed to cover a full-frame (36 x 24 mm) sensor. The larger optical elements in the SCT Corrector LF are designed to minimize vignetting, ensuring more even illumination from the center to the corners of your sensor.\u003c\/p\u003e\n\u003cp\u003eSome minor vignetting will remain, caused by the telescope's internal baffles which were designed for a slower native focal ratio. This effect is consistent and easily corrected during image processing with flat frames, leaving you with a clean, evenly illuminated final image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eCorrected Field: Reducing Native Spot Size by up to 9x\u003c\/h3\u003e\n\u003cp\u003eBeyond focal reduction, the SCT Corrector LF's main function is to eliminate the coma that naturally occurs in standard SCT designs. Sharpness is excellent over a 42mm diagonal. The improvement in sharpness is dramatic, with spot sizes up to 9 times smaller than the native telescope's optics can produce.\u003c\/p\u003e\n\u003cp\u003eOn a C14, for example, the RMS spot size at the edge of the field can measure 106 microns without correction. With the SCT Corrector LF installed, that same spot size is reduced to just 13 microns.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eImaging Train Design: 146mm of Available Backfocus\u003c\/h3\u003e\n\u003cp\u003eA significant advantage of the SCT Corrector LF is its generous 146mm of backfocus, measured from the top of the corrector's mounting threads. This substantial distance provides the flexibility to incorporate a wide range of accessories into your imaging train without compromising optical performance.\u003c\/p\u003e\n\u003cp\u003eThis space is critical for building a complete imaging system. You can easily fit components such as an \u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guider\u003c\/a\u003e (OAG), a \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheel\u003c\/a\u003e or \u003ca href=\"\/en-int\/collections\/filter-wheels-and-drawers\"\u003efilter drawer\u003c\/a\u003e, and any necessary adapters while still achieving the correct sensor distance for optimal correction. This makes it a practical solution for serious imagers with complex equipment needs.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eMechanical Interface: Attaching Accessories to the 3.29\" Rear Thread\u003c\/h3\u003e\n\u003cp\u003eTo maintain a robust connection throughout the imaging train, the rear of the SCT Corrector LF features the same 3.29\"-16 tpi male thread as the C11\/C14 rear cell itself. This allows you to attach standard large-format SCT accessories directly to the corrector.\u003c\/p\u003e\n\u003cp\u003eFor example, the Starizona \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-Adapter\u003c\/a\u003e with \u003ca href=\"\/en-int\/collections\/filter-accessories\"\u003eFilter Holder\u003c\/a\u003e for EdgeHD 9.25, C11 and C14 threads onto these 3.29\" threads. This adapter consumes 91mm of backfocus, leaving the standard 55mm spacing required for a DSLR with a T-ring or many dedicated astronomy cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eSCT Corrector LF vs. SCT Corrector IV: Full-Frame vs. APS-C\u003c\/h3\u003e\n\u003cp\u003eStarizona offers two versions of the SCT Corrector, designed for different sensor sizes and use cases. The choice depends on your camera's sensor format and your telescope.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eImage Circle:\u003c\/strong\u003e The LF model provides a 42mm image circle for full-frame sensors, while the standard SCT Corrector IV offers a 27mm image circle suitable for APS-C and smaller sensors.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBackfocus:\u003c\/strong\u003e The LF provides a long 146mm of backfocus for complex imaging trains. The SCT Corrector IV has a shorter backfocus of 90.3mm.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReduction:\u003c\/strong\u003e The LF is a 0.7x reducer. The SCT Corrector IV provides a slightly stronger 0.63x reduction.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting:\u003c\/strong\u003e The LF threads directly onto the C11\/C14's 3.29\" rear cell. The SCT Corrector IV uses a 2\" barrel, making it compatible with a wider range of SCTs via a 2\" \u003ca href=\"\/en-int\/collections\/visual-adapters\"\u003evisual back\u003c\/a\u003e or \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eBuild \u0026amp; Origin: 730g Machined Aluminum, Made in USA\u003c\/h3\u003e\n\u003cp\u003eThe SCT Corrector LF weighs 1.6 lb (730 g), measures 3.5\" at its widest and 2.7\" long (it adds 2.3\" beyond the mounting threads), and has fully AR coated optics.\u003c\/p\u003e\n\u003cp\u003eIt is made in the USA by Starizona.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the difference between the Starizona SCT Corrector LF and the SCT Corrector IV?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe SCT Corrector LF is designed for full-frame sensors on C11 and C14 SCTs, offering a 42mm image circle, 0.7x reduction, and 146mm of backfocus. The SCT Corrector IV is for APS-C or smaller sensors on a wider range of SCTs, with a 27mm image circle, 0.63x reduction, and 90.3mm of backfocus.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Starizona SCT Corrector LF with an EdgeHD telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. Starizona designs the SCT Corrector LF for standard (non-EdgeHD) Celestron C11 and C14 telescopes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I calculate the spacing for my camera with the SCT Corrector LF?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe SCT Corrector LF requires 146mm of backfocus, measured from the top of the corrector's mounting threads to your camera's sensor. You must add up the optical path length of all accessories in your imaging train (OAG, filter wheel, adapters) and use spacers to reach a total distance of 146mm.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Starizona SCT Corrector LF fully illuminate my full-frame sensor on a C14?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 42mm image circle is designed to cover a full-frame sensor. There is some remaining vignetting, limited by the telescope baffles, which are designed for a slower focal ratio. This is normal and is easily corrected by taking and applying flat calibration frames during image processing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I attach my DSLR camera to the SCT Corrector LF?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou will need an adapter that threads onto the corrector's 3.29-inch rear thread and provides the correct spacing. One option is the Starizona T-Adapter with Filter Holder for EdgeHD 9.25, C11 and C14, which has a 91mm optical length. This leaves the standard 55mm spacing needed for a DSLR and its corresponding T-ring.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Starizona SCT Corrector LF difficult to install?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eInstallation is straightforward. You simply unthread the standard visual back or adapter from your C11 or C14's 3.29-inch rear cell and thread the SCT Corrector LF directly on in its place. The more complex part is ensuring your complete imaging train meets the 146mm backfocus requirement.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat focal ratio and focal length does the SCT Corrector LF give on a C14?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eOn a Celestron C14 the SCT Corrector LF gives f\/7.2 and a 2560mm focal length, down from the C14's native f\/11.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow sharp is the SCT Corrector LF compared with the native telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eSpot sizes are up to 9 times smaller than the native telescope. At the edge of the field, the RMS spot size of a native C14 is 106 microns and just 13 microns with the SCT Corrector LF.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I attach standard large-SCT accessories behind the SCT Corrector LF?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. Its rear threads are the same 3.29\" threads as on the rear cell of the C11 and C14, so standard accessories attach easily.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow much length does the SCT Corrector LF add to my imaging train?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe corrector is 2.7\" long overall and adds 2.3\" beyond the telescope's normal mounting threads. Its maximum diameter is 3.5\".\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.7x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio \/ Focal Length on C11\u003c\/td\u003e\n\u003ctd\u003ef\/7, 1960 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio \/ Focal Length on C14\u003c\/td\u003e\n\u003ctd\u003ef\/7.2, 2560 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e42 mm (full-frame)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBackfocus\u003c\/td\u003e\n\u003ctd\u003e146 mm from top of mounting threads\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMounting Thread\u003c\/td\u003e\n\u003ctd\u003eCelestron C11\/C14 3.29\"-16 tpi (female)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear Thread\u003c\/td\u003e\n\u003ctd\u003e3.29\"-16 tpi, same as the C11\/C14 rear cell\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescopes\u003c\/td\u003e\n\u003ctd\u003eCelestron C11 and C14 standard SCTs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum Diameter\u003c\/td\u003e\n\u003ctd\u003e3.5\" (88.9 mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOverall Length\u003c\/td\u003e\n\u003ctd\u003e2.7\" (68.6 mm); adds 2.3\" beyond the mounting threads\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e730 g (1.6 lb)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Coatings\u003c\/td\u003e\n\u003ctd\u003eFully AR coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCountry of Manufacture\u003c\/td\u003e\n\u003ctd\u003eMade in USA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003e3.29\"-16tpi (Celestron C11\/C14 rear cell) female\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSCT Corrector LF\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/starizona-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eStarizona Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Starizona","offers":[{"title":"Default Title","offer_id":46905837224221,"sku":"STZ-SCTCORR-LF","price":699.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/image_652efa4f-9b28-4dc4-92b7-6752d1ea89a7.jpg?v=1698090461"},{"product_id":"sharpstar-50edph-0-84x-focal-reducer","title":"SharpStar 50EDPH 0.84x Focal Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces telescope focal ratio to f\/4.6\u003c\/li\u003e\n\u003cli\u003eConverts focal length to 230mm\u003c\/li\u003e\n\u003cli\u003eQuadruplet optical design with field flattening\u003c\/li\u003e\n\u003cli\u003eStandard 55mm back focus requirement\u003c\/li\u003e\n\u003cli\u003eConnects to cameras via M48x0.75 male thread\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eSharpStar 50EDPH 0.84x Focal Reducer\u003c\/h2\u003e\n\u003cp\u003eThe SharpStar 50EDPH 0.84x Focal Reducer is an essential accessory engineered specifically for the 50EDPH \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractor\u003c\/a\u003e, transforming it into a faster, wider imaging instrument. This quadruplet reducer converts the telescope to a 230mm focal length at a fast f\/4.6 focal ratio, all while maintaining a flat field. It establishes the standard 55mm back focus from its M48x0.75 threads and adds only 0.24kg to your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFaster, Wider Imaging at f\/4.6 for the 50EDPH\u003c\/h3\u003e\n\u003cp\u003eBy shortening the telescope's effective focal length to 230mm, this 0.84x reducer significantly widens your field of view. The corresponding focal ratio of f\/4.6 allows your camera sensor to gather light much more quickly, dramatically reducing exposure times required for faint deep-sky objects. This speed is critical for capturing expansive targets like the North American Nebula (NGC 7000) or large star clusters in a single frame.\u003c\/p\u003e\n\u003cp\u003eThe quadruplet optical design doesn't just reduce the focal length; it also acts as a \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003efield flattener\u003c\/a\u003e. This ensures that stars remain sharp and pinpoint across an APS-C sensor, correcting for the field curvature inherent in refractor optics and delivering a professional-grade image from edge to edge.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eOptimized for APS-C Sensors with 55mm Back Focus\u003c\/h3\u003e\n\u003cp\u003eThis reducer is engineered to fully illuminate APS-C sized sensors, making it a perfect match for a wide range of popular \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e and DSLRs. It features a standard M48x0.75 male thread for camera connection and requires a precise 55mm back focus distance from the base of this thread to your sensor for optimal performance.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandardized Connection:\u003c\/strong\u003e The 55mm back focus is the industry standard for most \u003ca href=\"\/en-int\/collections\/deep-sky-cameras\"\u003ecooled astronomy cameras\u003c\/a\u003e when used with their included adapters, simplifying your imaging train setup.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntegrated Filter Threads:\u003c\/strong\u003e The reducer includes internal M48x0.75 threads, allowing you to directly mount standard 2-inch astronomy filters without needing a separate \u003ca href=\"\/en-int\/collections\/filter-wheels-and-drawers\"\u003efilter drawer\u003c\/a\u003e.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLightweight Design:\u003c\/strong\u003e At just 0.24kg, the reducer adds minimal weight and leverage to the \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e, helping to maintain system rigidity and prevent tilt.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the SharpStar 0.84x reducer do for my 50EDPH telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt converts your SharpStar 50EDPH into a faster and wider imaging system. It changes the focal length to \u003cstrong\u003e230mm\u003c\/strong\u003e and the focal ratio to \u003cstrong\u003ef\/4.6\u003c\/strong\u003e. This allows for shorter exposure times and fitting larger celestial objects into your frame, while the quadruplet design also flattens the field for sharp stars edge-to-edge on APS-C sensors.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect my camera to the 50EDPH 0.84x Reducer to achieve the correct 55mm back focus?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer has a male M48x0.75 thread on the camera side. You must ensure the distance from the base of this thread to your camera's sensor is exactly \u003cstrong\u003e55mm\u003c\/strong\u003e. Most dedicated astronomy cameras and DSLR\/mirrorless cameras with a standard M48 \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e are designed to meet this 55mm spacing requirement with their included spacers.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2\" filters with this SharpStar 0.84x reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer has internal M48x0.75 threads, which is the standard threading for 2-inch astronomy filters. You can thread a filter directly into the reducer before attaching it to your camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the new focal length and focal ratio of the SharpStar 50EDPH with this 0.84x reducer installed?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWith the 0.84x reducer attached, the SharpStar 50EDPH has an effective focal length of \u003cstrong\u003e230mm\u003c\/strong\u003e and a focal ratio of \u003cstrong\u003ef\/4.6\u003c\/strong\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the SharpStar 50EDPH with the 0.84x reducer good for imaging the Andromeda Galaxy (M31) with an APS-C camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it's an excellent combination for that target. The resulting \u003cstrong\u003e230mm\u003c\/strong\u003e focal length provides a wide field of view that can frame the entirety of the Andromeda Galaxy (M31) and its satellite galaxies on a typical APS-C sensor, while the fast \u003cstrong\u003ef\/4.6\u003c\/strong\u003e focal ratio helps capture its faint dust lanes with shorter exposures.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the f\/4.6 focal ratio affect my exposures on faint targets like the Horsehead Nebula (Barnard 33)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003ef\/4.6\u003c\/strong\u003e focal ratio is significantly \"faster\" than the native f\/5.5 of the 50EDPH. For any given exposure time, you will collect roughly 43% more light. This means you can achieve the same signal-to-noise ratio in less time, which is a major advantage for capturing faint emission nebulae like the Horsehead Nebula (Barnard 33).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length (with 50EDPH)\u003c\/td\u003e\n\u003ctd\u003e230mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio (with 50EDPH)\u003c\/td\u003e\n\u003ctd\u003ef\/4.6\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eQuadruplet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired Back Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (from M48 thread base)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection Thread\u003c\/td\u003e\n\u003ctd\u003eM48×0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInternal Filter Thread\u003c\/td\u003e\n\u003ctd\u003eM48×0.75 (for 2\" filters)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.24kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification factor\u003c\/td\u003e\n\u003ctd\u003e0.84x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eM42x1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned for\u003c\/td\u003e\n\u003ctd\u003eSharpStar 50EDPH\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM48x0.75 male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSharpStar 50EDPH 0.84x Focal Reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eThreaded metal end caps\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 2\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSharpStar\/Askar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SharpStar Optics","offers":[{"title":"Default Title","offer_id":47477259370781,"sku":"SSO-SHREDU50","price":153.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/63ce6bdf-d283-4cde-9b2c-07d0617072e6.png?v=1705688490"},{"product_id":"askar-0-8x-reducer-for-140apo","title":"Askar 0.8x Reducer for 140APO","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces 140APO Focal Ratio to f\/5.6\u003c\/li\u003e\n\u003cli\u003eShortens 140APO Focal Length to 784mm\u003c\/li\u003e\n\u003cli\u003eStandard 55mm Back Focus Requirement\u003c\/li\u003e\n\u003cli\u003eTriplet Optical Design with Field Flattening\u003c\/li\u003e\n\u003cli\u003eIntegrated M48 (2-inch) Filter Thread\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 0.8x Reducer for 140APO\u003c\/h2\u003e\n\u003cp\u003eThe Askar 0.8x Reducer for \u003ca href=\"\/en-int\/products\/askar-140apo-f-7-triplet\"\u003e140APO\u003c\/a\u003e converts the telescope into a faster f\/5.6 imaging system with a 784mm focal length. This triplet reducer is engineered to maintain a standard 55mm back focus from its M48 male thread, simplifying camera connections. The 0.63kg assembly includes both M54×0.75 and M48×0.75 rear threads, with an integrated M48 filter thread inside for direct filter installation.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eTransforming the 140APO to an f\/5.6 Astrograph\u003c\/h3\u003e\n\u003cp\u003eBy reducing the native focal ratio of the Askar 140APO to f\/5.6, this corrector significantly cuts required exposure times, allowing you to gather more signal in less time. The triplet optical design simultaneously flattens the field for sharp stars across a full-frame sensor, while the shorter 784mm focal length provides a wider field of view for framing large targets like the Andromeda Galaxy (M31) or the North America Nebula (NGC 7000).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e55mm Back Focus and Flexible Connectivity\u003c\/h3\u003e\n\u003cp\u003eIntegrating the reducer into your imaging train is straightforward, thanks to the industry-standard 55mm back focus measured from the base of the M48 male thread. The reducer provides both M54×0.75 and M48×0.75 output threads for direct connection to a range of cameras and \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheels\u003c\/a\u003e. For added convenience, an internal M48×0.75 filter thread allows you to install 2-inch filters directly into the reducer itself, minimizing the components in your optical path.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Askar 0.8x Reducer change my field of view on the 140APO when imaging the Orion Nebula (M42)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer shortens the 140APO's focal length to \u003cstrong\u003e784mm\u003c\/strong\u003e, widening your field of view significantly. This allows you to capture the entire Orion Nebula complex, from the Trapezium Cluster to the fainter outer loops, in a single frame with a full-frame camera, which is difficult at the native focal length.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eI use an APS-C camera with my Askar 140APO. Is this reducer still a good choice?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. While designed to illuminate a full-frame sensor, the 0.8x Reducer provides excellent field flattening for smaller APS-C sensors. The main benefit is the speed increase to \u003cstrong\u003ef\/5.6\u003c\/strong\u003e, which reduces your sub-exposure times regardless of sensor size, helping to improve your signal-to-noise ratio on faint targets.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the back focus for the Askar 140APO 0.8x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe required back focus is a standard \u003cstrong\u003e55mm\u003c\/strong\u003e, measured from the base of the male M48x0.75 thread to your camera's sensor. This is compatible with most DSLR\/mirrorless cameras using a standard \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-ring\u003c\/a\u003e and many dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e with their included spacers.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2-inch filters with the Askar 0.8x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the reducer has a built-in \u003cstrong\u003eM48x0.75 filter thread\u003c\/strong\u003e on the camera side. This allows you to screw a standard 2-inch filter directly into the reducer housing, placing it securely within the optical path.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does this reducer attach to the Askar 140APO telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer is designed to thread directly onto the \u003ca href=\"\/en-int\/collections\/focusers\"\u003efocuser\u003c\/a\u003e of the Askar 140APO for a secure, tilt-free connection, ensuring perfect optical alignment.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the optical design of the Askar 140APO 0.8x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer uses a \u003cstrong\u003etriplet (3-element)\u003c\/strong\u003e air-spaced optical design. This configuration allows it to both reduce the focal length and correct for field curvature, providing sharp stars across the entire image field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/5.6\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Length\u003c\/td\u003e\n\u003ctd\u003e784mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eTriplet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (from base of M48 male thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Side Threads\u003c\/td\u003e\n\u003ctd\u003eM54×0.75 \u0026amp; M48×0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInternal Filter Threads\u003c\/td\u003e\n\u003ctd\u003eM48×0.75 (2-inch)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.63 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification factor\u003c\/td\u003e\n\u003ctd\u003e0.8x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage circle\u003c\/td\u003e\n\u003ctd\u003e44 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eM92x1 Male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned For\u003c\/td\u003e\n\u003ctd\u003eAskar 140APO\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 0.8x Reducer for 140APO\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eFront Dust Cap\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eRear Dust Cap\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_140APO_0.8x_Reducer_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":47636055032093,"sku":"ASK-ASKAR140R","price":461.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/7aa725af-9cf7-4e43-9110-3003e039fd08_1ac241f4-f6d7-4ae3-b7b3-93ea3908ef1e.jpg?v=1722021035"},{"product_id":"askar-1x-field-flattener-for-140apo","title":"Askar 1x Field Flattener for 140APO","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eEngineered for the Askar 140APO Triplet Refractor\u003c\/li\u003e\n\u003cli\u003e1x Flattener Preserves Native f\/7 Focal Ratio\u003c\/li\u003e\n\u003cli\u003eCorrects a 44mm Full-Frame Image Circle\u003c\/li\u003e\n\u003cli\u003eStandard 55mm Back Focus Requirement\u003c\/li\u003e\n\u003cli\u003eTriplet Optical Design for Sharp, Coma-Free Stars\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 1x Field Flattener for 140APO\u003c\/h2\u003e\n\u003cp\u003eThe Askar 1x Field Flattener is engineered specifically for the \u003ca href=\"\/en-int\/products\/askar-140apo-f-7-triplet\"\u003eAskar 140APO\u003c\/a\u003e \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractor\u003c\/a\u003e, maintaining the native 980mm focal length and f\/7 focal ratio of the telescope. Its triplet optical design corrects for field curvature across a 44mm full-frame image circle and establishes a standard 55mm back focus for seamless integration with your existing imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eTriplet Optics for a 44mm Corrected Image Circle\u003c\/h3\u003e\n\u003cp\u003eRefractor optics naturally produce a curved focal plane, resulting in elongated stars at the corners of an image. This 1x flattener uses a three-element, air-spaced triplet lens system to counteract this effect, ensuring pinpoint stars across the entire field of a full-frame sensor. By supporting a 44mm image circle, you can leverage large-format CMOS and CCD cameras without significant vignetting or distortion at the edges.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e55mm Back Focus and Flexible Camera Connections\u003c\/h3\u003e\n\u003cp\u003eDesigned for straightforward integration, this flattener requires a standard 55mm back focus from the base of its M48 male thread. This spacing is compatible with most ZWO, QHY, and other dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy cameras\u003c\/a\u003e when used with their stock adapters, as well as with standard DSLR\/mirrorless \u003ca href=\"\/en-int\/collections\/imaging-adapters\"\u003eT-rings\u003c\/a\u003e. The 0.79kg unit provides multiple camera-side connections, including M68×1, M54×0.75, and M48×0.75 threads, and features internal M48 threads for mounting 2-inch filters within the optical path.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the purpose of the Askar 1x Field Flattener for the 140APO?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIts primary purpose is to correct the natural field curvature of the Askar 140APO refractor. This correction ensures that stars are sharp and round not just in the center of your image, but all the way to the corners, which is essential for astrophotography with modern large-format sensors.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes this Askar flattener change the focal length of my 140APO?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. This is a \u003cstrong\u003e1x flattener\u003c\/strong\u003e, meaning it does not reduce or extend the focal length. When attached to the Askar 140APO, the telescope's focal length remains 980mm and the focal ratio stays at f\/7.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Askar 1x flattener improve images of the Andromeda Galaxy (M31) with the 140APO?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA large target like the Andromeda Galaxy (M31) will fill the frame of a full-frame sensor on the 140APO. Without the flattener, stars in the outer arms and surrounding the galaxy would appear stretched. With the flattener's 44mm corrected circle, the part of the galaxy that falls on the sensor, and the starfield around it, will be rendered with sharp, pinpoint stars from edge to edge.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I achieve the correct 55mm back focus with the Askar 1x Flattener?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 55mm distance is measured from the base of the flattener's M48 male thread to your camera's sensor. Most dedicated astronomy cameras and DSLR\/mirrorless cameras with a T-ring are designed to meet this 55mm standard using a combination of included extension rings. You must ensure your total imaging train (\u003ca href=\"\/en-int\/collections\/autoguiding\"\u003eoff-axis guider\u003c\/a\u003e, \u003ca href=\"\/en-int\/collections\/filter-wheels\"\u003efilter wheel\u003c\/a\u003e, etc.) adds up to exactly 55mm for optimal performance.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2\" filters with the Askar 140APO flattener?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The flattener has a built-in M48×0.75 filter thread on the telescope side of the camera adapters. This allows you to directly screw in any standard 2-inch astronomy filter for light pollution reduction or narrowband imaging.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Askar 1x flattener work on telescopes other than the 140APO?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this flattener is optically matched specifically for the Askar 140APO triplet refractor. Using it with other telescopes will likely result in poor field correction and degraded image quality. For other telescopes, you should use the flattener designed for that specific optical system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e3-Element Triplet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification\u003c\/td\u003e\n\u003ctd\u003e1x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescope\u003c\/td\u003e\n\u003ctd\u003eAskar 140APO\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length (with 140APO)\u003c\/td\u003e\n\u003ctd\u003e980mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio (with 140APO)\u003c\/td\u003e\n\u003ctd\u003ef\/7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCorrected Image Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (from base of M48 male thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connections\u003c\/td\u003e\n\u003ctd\u003eM68×1, M54×0.75, M48×0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thread\u003c\/td\u003e\n\u003ctd\u003eInternal M48×0.75 (for 2\" filters)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.79kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-side connection\u003c\/td\u003e\n\u003ctd\u003eM92x1 Male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM68x1 male, M54x0.75 male, M48x0.75 (2\" filter) male, M48x0.75 (2\" filter) female\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 1x Field Flattener for 140APO\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_140APO_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":47636067615005,"sku":"ASK-ASKAR140FL","price":461.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/4930810f-9de1-46ee-a4ba-28f63ecc8ddd.png?v=1722023524"},{"product_id":"askar-0-75x-71f-reducer","title":"Askar 0.75x 71F Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e0.75x Reduction Factor\u003c\/li\u003e\n\u003cli\u003eTransforms Askar 71F to f\/5.2\u003c\/li\u003e\n\u003cli\u003eNew Focal Length: 369mm\u003c\/li\u003e\n\u003cli\u003eStandard 55mm Back Focus\u003c\/li\u003e\n\u003cli\u003eTriplet Optical Design\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 0.75x 71F Reducer\u003c\/h2\u003e\n\u003cp\u003eThe Askar 0.75x 71F Reducer transforms the Askar 71F \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractor\u003c\/a\u003e into a faster f\/5.2 imaging system with a new focal length of 369mm. This triplet reducer provides a standard 55mm back focus for easy camera integration and weighs just 0.23kg.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA Faster Askar 71F: The 0.75x Reduction to f\/5.2\u003c\/h3\u003e\n\u003cp\u003eBy reducing the native focal ratio of the Askar 71F to f\/5.2, this corrector significantly shortens required exposure times, allowing you to gather more signal on faint targets in a single session. The resulting 369mm focal length creates a wider field of view, ideal for framing large emission nebulae like the North American Nebula (NGC 7000) or sprawling star clusters. Its triplet optical design is engineered specifically to maintain image sharpness across the field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFull-Frame Correction with 55mm Standard Back Focus\u003c\/h3\u003e\n\u003cp\u003eThis reducer is also a dedicated \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003efield flattener\u003c\/a\u003e, designed to produce sharp stars out to the corners of full-frame sensors. Imaging integration is straightforward thanks to a standard 55mm back focus, measured from the base of its M48 male thread, simplifying connection to your DSLR or dedicated \u003ca href=\"\/en-int\/collections\/cameras\"\u003eastronomy camera\u003c\/a\u003e. The 71F photographic extension tube adapter that connects to the reducer has a built-in M48x0.75 2-inch filter thread, allowing you to use light pollution or \u003ca href=\"\/en-int\/collections\/narrowband-filters\"\u003enarrowband filters\u003c\/a\u003e without adding extra spacing to your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main benefit of using the Askar 0.75x Reducer with my 71F telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary benefit is speed. It reduces the focal ratio to f\/5.2, which cuts your exposure times significantly compared to the native f\/6.9 ratio. This allows you to collect more data on faint objects in less time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect my camera to the Askar 71F 0.75x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer provides a standard \u003cstrong\u003e55mm back focus\u003c\/strong\u003e from the base of its M48 male thread. You will need to use a combination of M48 spacers and adapters to place your camera's sensor at exactly this distance to achieve a flat field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs this Askar 0.75x reducer suitable for imaging the Andromeda Galaxy (M31) with a full-frame camera on the 71F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reduced focal length of \u003cstrong\u003e369mm\u003c\/strong\u003e provides a wide field of view that is excellent for large targets like the Andromeda Galaxy (M31) or the Heart and Soul Nebulae. The reducer is designed to flatten the field for full-frame sensors, ensuring sharp stars across the entire frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Askar 0.75x 71F Reducer also work as a field flattener?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it is a reducer-flattener. Its \u003cstrong\u003etriplet optical design\u003c\/strong\u003e corrects for field curvature, ensuring that stars are sharp from the center to the edges of the image, which is critical for astrophotography.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2-inch filters with the Askar 0.75x Reducer on my 71F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The 71F photographic extension tube adapter that connects to the reducer has a built-in 2-inch (M48x0.75) filter thread. You can thread them directly into the imaging train, making it easy to use narrowband or \u003ca href=\"\/en-int\/collections\/light-pollution-filters\"\u003elight pollution filters\u003c\/a\u003e for targets like the Orion Nebula (M42).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the image circle of the Askar 0.75x 71F Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer is designed as a full-frame corrector. It effectively illuminates and flattens the field for camera sensors up to a 35mm format (43mm diagonal), making it compatible with a wide range of DSLRs and dedicated astronomy cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.75x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Length (with 71F)\u003c\/td\u003e\n\u003ctd\u003e369mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Ratio (with 71F)\u003c\/td\u003e\n\u003ctd\u003ef\/5.2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eTriplet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (from the base of M48 male thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear Thread\u003c\/td\u003e\n\u003ctd\u003eM59*1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.23kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM59x1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesigned For\u003c\/td\u003e\n\u003ctd\u003eAskar 71F\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 0.75x 71F Reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software \u0026amp; Drivers\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":49200895263005,"sku":"ASK-ASKAR71R","price":291.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-Reducer-71F-1.jpg?v=1727375509"},{"product_id":"david-astro-universal-field-flattener-2","title":"David Astro Universal Field Flattener - 2\"","description":"\u003cul\u003e\n\u003cli\u003e55mm back focus\u003c\/li\u003e\n\u003cli\u003eWorks with f\/5 to f\/7 refractors\u003c\/li\u003e\n\u003cli\u003eCompatible with APS-C size cameras or smaller.\u003c\/li\u003e\n\u003cli\u003eAccepts 2\" filters\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cp\u003eOptimized for \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e with focal ratios of f\/5 to f\/7, the David Astro 1.0x \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003eField Flattener\u003c\/a\u003e performs best with APS-C sensor cameras. It’s also compatible with slightly faster or slower refractors when used with smaller 1” and 4\/3” sensors, offering flexibility for various imaging setups. The flattener features standard M42x0.75 T\/T2 threads for easy connection to the camera and a 38mm clear aperture, perfectly suited for APS-C sensors and smaller.\u003c\/p\u003e","brand":"David Astro","offers":[{"title":"Default Title","offer_id":49365678129437,"sku":"DAV-FF1.0X","price":175.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/DAV-FF1-0X-1.jpg?v=1731529781"},{"product_id":"david-astro-0-8x-universal-reducer-2","title":"David Astro 0.8x Universal Reducer - 2\"","description":"\u003cul\u003e\n\u003cli\u003e55mm back focus\u003c\/li\u003e\n\u003cli\u003eWorks with f\/5 to f\/7 refractors\u003c\/li\u003e\n\u003cli\u003eCompatible with APS-C size cameras or smaller.\u003c\/li\u003e\n\u003cli\u003eAccepts 2\" filters\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cp\u003eOptimized for \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e with focal ratios of f\/5 to f\/7, the David Astro 0.8x \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003eField Flattener\u003c\/a\u003e performs best with APS-C sensor cameras. It’s also compatible with slightly faster or slower refractors when used with smaller 1” and 4\/3” sensors, offering flexibility for various imaging setups. The flattener features standard M42x0.75 T\/T2 threads for easy connection to the camera and a 38mm clear aperture, perfectly suited for APS-C sensors and smaller.\u003c\/p\u003e","brand":"David Astro","offers":[{"title":"Default Title","offer_id":49365679898909,"sku":"DAV-FF0.8X","price":175.0,"currency_code":"CAD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/DAV-FF08X-1.jpg?v=1731530735"},{"product_id":"david-astro-0-6x-universal-reducer-2","title":"David Astro 0.6x Universal Reducer - 2\"","description":"\u003cul\u003e\n\u003cli\u003e55mm back focus\u003c\/li\u003e\n\u003cli\u003eWorks with f\/5 to f\/7 refractors\u003c\/li\u003e\n\u003cli\u003eCompatible with APS-C size cameras or smaller.\u003c\/li\u003e\n\u003cli\u003eAccepts 2\" filters\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cp\u003eOptimized for \u003ca href=\"\/en-int\/collections\/refractors\"\u003erefractors\u003c\/a\u003e with focal ratios of f\/5 to f\/7, the David Astro 0.6x \u003ca href=\"\/en-int\/collections\/flatteners-and-reducers\"\u003eField Flattener\u003c\/a\u003e performs best with APS-C sensor cameras. It’s also compatible with slightly faster or slower refractors when used with smaller 1” and 4\/3” sensors, offering flexibility for various imaging setups. The flattener features standard M42x0.75 T\/T2 threads for easy connection to the camera and a 38mm clear aperture, perfectly suited for APS-C sensors and smaller.\u003c\/p\u003e","brand":"David Astro","offers":[{"title":"Default Title","offer_id":49365682389277,"sku":"DAV-FF0.6X","price":199.0,"currency_code":"CAD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/DAV-FF06X-1.jpg?v=1731530783"},{"product_id":"starizona-hyperstar-v4-for-celestron-11","title":"Starizona HyperStar V4 for Celestron 11\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eConverts Celestron 11\" SCT\/EdgeHD to an f\/1.9 imaging system\u003c\/li\u003e\n\u003cli\u003e540mm focal length for wide-field astrophotography\u003c\/li\u003e\n\u003cli\u003eDelivers a 3.7° coma-free, flat field of view\u003c\/li\u003e\n\u003cli\u003eCovers sensors up to 35mm diagonal\u003c\/li\u003e\n\u003cli\u003eStandard adapter provides 17.5mm backfocus with M42 threads\u003c\/li\u003e\n\u003cli\u003eAllows for unguided imaging, even on alt-azimuth mounts\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eStarizona HyperStar V4 for Celestron 11\"\u003c\/h2\u003e\n\u003cp\u003eThe Starizona HyperStar V4 for Celestron 11\" replaces your telescope's secondary mirror, converting it from a slow f\/10 system into an incredibly fast f\/1.9 \u003ca href=\"\/en-int\/collections\/astrograph-telescopes\"\u003eastrograph\u003c\/a\u003e. This transformation shortens the focal length to just 540mm, yielding a massive 3.7° field of view that is coma-free and flat for sensors up to 35mm. Working 25 times faster than the native telescope, the HyperStar 11 makes it possible to capture deep-sky images with dramatically shorter exposures; no guiding and no \u003ca href=\"\/en-int\/collections\/equatorial-wedges\"\u003eequatorial wedge\u003c\/a\u003e are required.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFrom f\/10 to a 25x Faster f\/1.9 Imaging System\u003c\/h3\u003e\n\u003cp\u003eThe core function of the HyperStar 11 is to radically increase the light-gathering speed of your Celestron 11\" SCT. By operating at a focal ratio of f\/1.9, the system becomes approximately 25 times faster than the telescope's native f\/10 configuration. This dramatic reduction in exposure time is the single most significant advantage of prime-focus imaging.\u003c\/p\u003e\n\u003cp\u003eShort sub-exposures make tracking errors far less critical, which is why no guiding and no equatorial wedge are required, including on \u003ca href=\"\/en-int\/collections\/alt-azimuth-mounts\"\u003ealt-azimuth\u003c\/a\u003e fork mounts.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 540mm Focal Length with a 3.7° Coma-Free Field\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar 11 lens assembly reduces the C11's focal length to 540mm, transforming it into a powerful wide-field instrument. This optical configuration produces a vast field of view up to 3.7° across, allowing you to frame enormous targets like the Andromeda Galaxy (M31) or the entire Veil Nebula complex in a single shot.\u003c\/p\u003e\n\u003cp\u003eStarizona's fully multi-coated optics deliver a coma-free, flat field for sensors up to 35mm in \u003ca href=\"\/en-int\/collections\/diagonals\"\u003ediagonal\u003c\/a\u003e, which covers APS-C cameras (a full-frame sensor, about 43mm diagonal, is larger).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eC11 \u0026amp; EdgeHD 11 Fastar Compatibility\u003c\/h3\u003e\n\u003cp\u003eThe HyperStar V4 is designed for any Fastar-compatible Celestron 11\" \u003ca href=\"\/en-int\/collections\/schmidt-cassegrain-telescopes\"\u003eSchmidt-Cassegrain telescope\u003c\/a\u003e. These models feature a secondary mirror that can be unthreaded and removed, allowing the HyperStar lens to be installed in its place. The process is fully reversible, letting you switch between f\/1.9 imaging and f\/10 visual or planetary work.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard C11 SCT:\u003c\/strong\u003e Mounts directly to any Fastar-compatible C11 optical tube.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEdgeHD 11:\u003c\/strong\u003e The included EdgeHD Adapter Ring fits the same HyperStar unit to Celestron EdgeHD 11 optical tubes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOlder Non-Fastar Telescopes:\u003c\/strong\u003e If you have an older C11 without a removable secondary, the HyperStar Conversion Kit (sold separately) allows the telescope to be retrofitted for HyperStar compatibility.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e17.5mm Backfocus: Camera Adapters and the Filter Slider Upgrade\u003c\/h3\u003e\n\u003cp\u003eAt f\/1.9, achieving precise camera backfocus is critical for a sharp image across the field. The HyperStar 11 system is designed around a standard 17.5mm backfocus distance, which covers most popular cooled astrocameras.\u003c\/p\u003e\n\u003cp\u003eThe standard configuration includes a Standard Camera Adapter with an M42 male top that accepts one 2\" (M48) mounted filter. For enhanced flexibility, an optional Filter Slider Upgrade is available. It comes with its own HyperStar Filter Slider Adapter for 17.5mm backfocus cameras and swappable M42 and M54 male top plates.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eInstallation, Collimation, and Independent Camera Rotation\u003c\/h3\u003e\n\u003cp\u003eSwitching from visual observing to HyperStar imaging is a straightforward process. The C11's secondary mirror is removed and stored in the included Secondary Mirror Holder, and the HyperStar lens takes its place.\u003c\/p\u003e\n\u003cp\u003eThe HyperStar lens features built-in collimation adjustment screws, allowing you to fine-tune the optical alignment. Independent camera rotation lets you frame your target without moving the lens.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003ePrecision Focusing and Mount Balance at f\/1.9\u003c\/h3\u003e\n\u003cp\u003eThe extremely fast f\/1.9 focal ratio creates a very narrow critical focus zone, demanding precise focus adjustments. While not difficult, achieving perfect focus requires the right tools. A \u003ca href=\"\/en-int\/collections\/focusing-masks\"\u003eBahtinov mask\u003c\/a\u003e is highly effective, and software-assisted focusing using FWHM (Full-Width Half-Max) measurements with an \u003ca href=\"\/en-int\/collections\/electronic-focusers\"\u003eelectronic focuser\u003c\/a\u003e will yield the best results.\u003c\/p\u003e\n\u003cp\u003eAttaching the 2.1 lb HyperStar and a camera to the front of the telescope shifts the center of balance forward. On a \u003ca href=\"\/en-int\/collections\/equatorial-mounts\"\u003eGerman equatorial mount\u003c\/a\u003e, you can simply slide the optical tube forward in its cradle to re-balance. However, on a fork-mounted alt-azimuth telescope like a Celestron CPC or Evolution, the HyperStar \u003ca href=\"\/en-int\/collections\/counterweights\"\u003eCounterweight\u003c\/a\u003e (sold separately) fits into the 1.25\" visual back to balance the lens and camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eHyperStar 11 vs. HyperStar 8: Sensor Size and Field of View\u003c\/h3\u003e\n\u003cp\u003eWhile both the HyperStar 11 and its smaller sibling, the HyperStar 8, convert their respective telescopes to an f\/1.9 focal ratio, their intended applications differ based on the telescope's aperture.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum Sensor Size:\u003c\/strong\u003e The HyperStar 11 offers a significant advantage here, with a 35mm maximum sensor size. The HyperStar 8 is limited to a maximum sensor size of 28mm, making it better suited for APS-C and smaller format cameras.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocal Length and Field of View:\u003c\/strong\u003e The HyperStar 11 provides a longer focal length of 540mm compared to the HyperStar 8's 390mm. This gives a larger image scale and a slightly narrower field of view (3.7° vs. 4.1°).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need the Filter Slider to use filters with the HyperStar 11?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The Standard Camera Adapter included with the HyperStar 11 accepts one 2\" (M48) mounted filter. This is perfect for using a single light pollution or \u003ca href=\"\/en-int\/collections\/dual-band-filters\"\u003edual-band filter\u003c\/a\u003e with a one-shot-color camera. The Filter Slider is an optional upgrade that is most useful for monochrome imagers who need to quickly swap between multiple filters (like LRGB or narrowband) during an imaging session.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat cameras work with the included HyperStar 11 adapter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe included Standard Camera Adapter is designed for cameras that have 17.5mm of backfocus and standard M42 T-threads. This covers most popular cooled astrocameras. If your camera has a different backfocus distance or requires a different thread size (like M54), other adapters are available separately.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs focusing the HyperStar 11 difficult at f\/1.9?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFocusing at f\/1.9 is more sensitive than at f\/10, but it is not difficult with the right technique. The critical focus zone is very small, so manual focusing must be done carefully. A Bahtinov mask, an autofocuser, or software that shows star FWHM all work well.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the HyperStar 11 work on my older Celestron 11\" SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt depends. The HyperStar 11 is designed for Fastar-compatible Celestron 11\" telescopes, which have a removable secondary mirror. If you have an older, non-Fastar model , the HyperStar Conversion Kit (sold separately) makes it compatible; old orange-tube C11s need a modified version of the kit.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I balance my CPC 1100 Deluxe HD with the HyperStar 11 attached?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eSince you cannot slide the optical tube on a fork-mounted telescope like the CPC 1100, you will need a counterweight. The HyperStar Counterweight (sold separately) fits into the 1.25\" visual back at the rear of the telescope to balance the HyperStar and camera on the front.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use my full-frame DSLR with the HyperStar 11?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNot for its full sensor. The maximum sensor size is 35mm, smaller than a full-frame sensor (about 43mm diagonal). DSLR adapters are sold separately and do not work with the Filter Slider.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the purpose of the included EdgeHD Adapter Ring?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe EdgeHD Adapter Ring fits the same HyperStar 11 unit to an EdgeHD 11 optical tube, so one lens works on both a standard C11 and an EdgeHD 11.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need to collimate the HyperStar 11 every time I use it?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eHow often collimation is needed is not specified. The lens has adjustable collimation, and with the HyperStar Conversion Kit the secondary mirror's collimation is retained when it is removed for HyperStar imaging.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill I need spacers to get the 17.5mm backfocus correct?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The HyperStar 11 ships with the correct adapter pre-set for a 17.5mm backfocus. There are no spacers to install. Simply thread your camera directly onto the adapter, and the spacing will be correct.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eHyperStar 11 (C11 v4)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/1.9\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e540 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eField of View\u003c\/td\u003e\n\u003ctd\u003eUp to 3.7°, coma-free, flat field\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Sensor Size\u003c\/td\u003e\n\u003ctd\u003e35 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescopes\u003c\/td\u003e\n\u003ctd\u003eFastar-compatible Celestron C11 SCT (older C11 with the HyperStar Conversion Kit, sold separately); Celestron EdgeHD 11 with the included EdgeHD Adapter Ring\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Backfocus (included adapter)\u003c\/td\u003e\n\u003ctd\u003e17.5 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIncluded Adapter Threads\u003c\/td\u003e\n\u003ctd\u003eM42 male top (M54 top sold separately)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilters\u003c\/td\u003e\n\u003ctd\u003eOne 2\" (M48) mounted filter in the Standard Camera Adapter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptional Filter Slider Threads\u003c\/td\u003e\n\u003ctd\u003eM42 male and M54 male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLength\u003c\/td\u003e\n\u003ctd\u003e4.5\" (without camera adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDiameter\u003c\/td\u003e\n\u003ctd\u003e4.3\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003eApprox. 2.1 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Coatings\u003c\/td\u003e\n\u003ctd\u003eFully multi-coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFinish\u003c\/td\u003e\n\u003ctd\u003eBlack anodized\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCollimation\u003c\/td\u003e\n\u003ctd\u003eAdjustable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Rotation\u003c\/td\u003e\n\u003ctd\u003eIndependent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCountry of Manufacture\u003c\/td\u003e\n\u003ctd\u003eMade in U.S.A. (Tucson, Arizona)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMagnification Factor\u003c\/td\u003e\n\u003ctd\u003eConverts f\/10 to f\/1.9 (prime focus)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope-Side Connection\u003c\/td\u003e\n\u003ctd\u003ereplaces the Fastar-compatible secondary mirror assembly\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera-Side Connection\u003c\/td\u003e\n\u003ctd\u003eM42x0.75 (T2) male\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eHyperStar 11 (C11 v4) lens\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eEdgeHD Adapter Ring\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eStandard Camera Adapter, M42 male top, 17.5 mm backfocus (No Filter Slider version)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSecondary Mirror Holder\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eFilter Slider Upgrade (Add Filter Slider version): Filter Slider, M42 male plate with dust cap, M48 female plate, M54 male plate with dust cap, HyperStar Filter Slider Adapter for 17.5 mm backfocus cameras\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/starizona-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eStarizona Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Starizona","offers":[{"title":"No Filter Slider","offer_id":49476258431261,"sku":"STZ-HS4-C11","price":1818.0,"currency_code":"CAD","in_stock":true},{"title":"Add Filter Slider","offer_id":49476258464029,"sku":"STZ-HS4-C11-FS","price":1999.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Starizona-Hyperstar-11_c8dc9f82-bc96-4304-8229-f674616e4038.jpg?v=1734570734"}],"url":"https:\/\/davidastro.com\/en-int\/collections\/flatteners-and-reducers.oembed","provider":"David Astro","version":"1.0","type":"link"}