{"product_id":"askar-m54-oag","title":"Askar M54 Off-Axis Guider (OAG)","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eLarge 10mm x 10mm guide prism\u003c\/li\u003e\n\u003cli\u003eM54, M48, and M42 adapters provide broad compatibility\u003c\/li\u003e\n\u003cli\u003eOptimized for full-frame cameras\u003c\/li\u003e\n\u003cli\u003eRigid CNC-machined construction\u003c\/li\u003e\n\u003cli\u003eEliminates differential flexure for sharper guiding\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\u003eAskar M54 Off-Axis Guider (OAG)\u003c\/h2\u003e\n\u003cp\u003eThe Askar M54 Off-Axis Guider (OAG) solves differential flexure by sampling the same light path as your main imaging camera, using a large 10mm x 10mm prism to intercept guide stars at the edge of the corrected field. With included M54, M48, and M42 threaded adapters, this OAG integrates directly into your full-frame imaging train, providing rigid, accurate guiding without the need for a separate guide scope.\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 10x10mm Prism for Brighter Guide Stars\u003c\/h3\u003e\n\u003cp\u003eThe core of the Askar OAG is its oversized 10mm x 10mm prism. This large surface area collects significantly more light than smaller prisms, increasing the brightness of potential guide stars and expanding your selection, which is critical when imaging in star-poor regions of the sky. This makes it easier to find and lock onto a suitable guide star without having to rotate the entire 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\u003eM54, M48 \u0026amp; M42 Adapters for Full-Frame Setups\u003c\/h3\u003e\n\u003cp\u003eDesigned for the modern astrophotographer, the Askar M54 OAG features a large clear aperture to prevent vignetting on full-frame sensors. It includes a versatile set of threaded adapters—M54, M48 (2-inch filter thread), and M42 (T-thread)—ensuring seamless integration with a wide variety of flatteners, reducers, and cameras. The entire body is CNC machined for maximum rigidity, ensuring your guide camera and imaging camera move as a single, solid unit.\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 Askar M54 OAG's 10x10mm prism?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe large \u003cstrong\u003e10mm x 10mm prism\u003c\/strong\u003e gathers more light, making it easier to find and lock onto fainter guide stars. This is a significant advantage over smaller prisms, especially when using narrowband filters or imaging in areas of the sky with few bright stars.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Askar M54 OAG cause vignetting with my full-frame camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, the Askar M54 OAG is specifically designed with a large clear aperture to fully illuminate full-frame sensors (24mm x 36mm). When correctly installed, the prism sits just outside the main imaging sensor's light path, preventing any shadowing or vignetting on your final image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich adapters are included with the Askar M54 OAG?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar M54 OAG includes three of the most common threaded adapters used in astrophotography:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eM54 x 0.75:\u003c\/strong\u003e For connecting to large-format flatteners and correctors.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM48 x 0.75:\u003c\/strong\u003e The standard for 2\" filters and many full-frame correctors.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM42 x 0.75:\u003c\/strong\u003e The universal T-thread for connecting to smaller cameras and accessories.\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 Askar M54 OAG improve guiding over a separate guide scope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAn Off-Axis Guider eliminates \u003cstrong\u003edifferential flexure\u003c\/strong\u003e, which is tiny mechanical sagging or shifting between the main telescope and a separate guide scope. By using the same optical tube for both imaging and guiding, the OAG ensures that any movement detected by the guide camera is the exact same movement affecting the imaging camera, resulting in sharper, rounder stars during long exposures.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Askar M54 OAG to guide on targets like the Andromeda Galaxy (M31) with my wide-field refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, absolutely. For large targets like the Andromeda Galaxy (M31), the Askar OAG's large prism makes it easy to find a suitable guide star in the periphery of your field of view while you frame the galaxy's core on your main sensor. This setup is ideal for capturing wide-field mosaics and deep images of expansive nebulae and galaxies.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Askar M54 OAG difficult to set up for a beginner?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile OAGs require more initial setup than a guide scope (specifically, achieving simultaneous focus between the imaging and guide cameras), the Askar M54 OAG is designed to be user-friendly. The included adapters simplify connection, and the large prism makes the challenging task of finding a guide star much easier for those new to off-axis guiding.\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\u003ePrism Size\u003c\/td\u003e\n\u003ctd\u003e10mm x 10mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Side Threads\u003c\/td\u003e\n\u003ctd\u003eM54x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Side Threads\u003c\/td\u003e\n\u003ctd\u003eM54x0.75, M48x0.75, M42x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Support\u003c\/td\u003e\n\u003ctd\u003eFull-Frame Compatible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConstruction\u003c\/td\u003e\n\u003ctd\u003eCNC Machined Aluminum\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 M54 Off-Axis Guider\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 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\"\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\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eM42 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\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":52851342147869,"sku":"ASK-ASKAROAG","price":197.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-Off-axis-Guider-OAG-1_7a7f02f4-1900-4056-830e-a70d82de66ff.jpg?v=1788401846","url":"https:\/\/davidastro.com\/fr-eu\/products\/askar-m54-oag","provider":"David Astro","version":"1.0","type":"link"}