{"product_id":"tele-vue-0-8x-focal-reducer","title":"Tele Vue 0.8x Focal Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduction Factor: 0.8x\u003c\/li\u003e\n\u003cli\u003eOptical Design: Reducer and Field Flattener\u003c\/li\u003e\n\u003cli\u003eTelescope Connection: 2-inch Barrel\u003c\/li\u003e\n\u003cli\u003eCamera Connection: M42x0.75 T-Ring Thread\u003c\/li\u003e\n\u003cli\u003eOptimal Back Focus: 56mm\u003c\/li\u003e\n\u003cli\u003eCompatible Telescopes: Tele Vue refractors up to 800mm focal length\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\u003eManuals\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\u003eCapture Wider Fields and Fainter Detail with Your Tele Vue Refractor\u003c\/h2\u003e\n\u003cp\u003eThe Tele Vue 0.8x Focal Reducer (TRF-2008) is an essential imaging accessory designed specifically to enhance the deep-sky performance of Tele Vue refractors. This optically matched reducer and field flattener shortens your telescope's effective focal length by 20%, creating a wider, faster imaging system. The result is a dramatic increase in field of view and a significant reduction in required exposure time, allowing you to capture expansive nebulae and faint galaxies 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\u003eThe 0.8x Reduction Advantage for Deep-Sky Imaging\u003c\/h3\u003e\n\u003cp\u003eThe core of the TRF-2008 is its 0.8x reduction lens assembly. By shortening your telescope's focal length, it also reduces the focal ratio. A 600mm f\/7.5 refractor, for example, becomes a 480mm f\/6 system. This \"faster\" optical system concentrates the same amount of light onto a smaller area of your camera sensor, reducing required exposure times by approximately 36%. This allows you to gather more data in a single night or capture fainter details without pushing your mount's tracking limits.\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 Pinpoint Stars Across the Entire Frame\u003c\/h3\u003e\n\u003cp\u003eBeyond simple reduction, the TRF-2008 is a dedicated field flattener. Refracting telescopes naturally produce a curved focal plane, which can result in slightly elongated stars at the edges of an image. This reducer incorporates corrective optics that counteract this effect, ensuring that stars remain tight, round points from the center of your sensor to the corners. This is the mechanism that delivers sharp, professional-looking astrophotographs without the need for excessive cropping.\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 with Your Imaging Train\u003c\/h3\u003e\n\u003cp\u003eEngineered for a perfect fit, the TRF-2008 slides directly into any standard 2-inch focuser drawtube. The barrel is threaded to accept standard 48mm (2-inch) astronomy filters, allowing you to easily incorporate light pollution or narrowband filters into your setup without adding complex adapters. This thoughtful design simplifies your imaging train and maintains a secure, rigid connection between the telescope and your 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\u003eStandard T-Ring Connection for Universal Camera Compatibility\u003c\/h3\u003e\n\u003cp\u003eThe camera side of the TRF-2008 features a male M42x0.75 T-thread, the universal standard for attaching imaging equipment. This allows you to connect virtually any DSLR or dedicated CMOS\/CCD astronomy camera using a standard T-ring. This direct, threaded connection is far more secure than set-screw or compression ring systems, preventing camera sag or tilt that can ruin a long exposure.\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 Critical Role of 56mm Back Focus\u003c\/h3\u003e\n\u003cp\u003eFor the field-flattening optics to perform correctly, the distance from the reducer's rear flange to your camera's sensor must be 56mm (+\/-2mm). This is a critical specification, not a guideline. Most DSLRs with a standard T-ring naturally hit this spacing, but for dedicated astronomy cameras, you may need to use T-threaded extension tubes to achieve this precise distance. Nailing this back focus is the key to unlocking the reducer's edge-to-edge sharpness.\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\u003eMaximizing Light and Contrast with Multi-Coatings\u003c\/h3\u003e\n\u003cp\u003eEvery air-to-glass surface in the TRF-2008 optical path is treated with Tele Vue's proprietary multi-coatings. These advanced coatings are designed to maximize light transmission, ensuring that the faint light from distant galaxies and nebulae reaches your sensor. They also serve to suppress internal reflections, which would otherwise reduce image contrast and introduce ghosting artifacts on bright stars.\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 Tele Vue Refractors\u003c\/h3\u003e\n\u003cp\u003eIt is important to note that the TRF-2008's optical prescription is specifically calculated to correct the field curvature of Tele Vue refractors with focal lengths of 400mm to 800mm, like the TV-76 and TV-85. While it may function with other short refractors, performance is not guaranteed. This specialization is its primary trade-off; it exchanges universal compatibility for exceptional performance within its designed system. Using it with a longer focal length scope, like the NP101is or NP127is, will result in vignetting.\u003c\/p\u003e\n\u003cp\u003eImagine framing the entirety of the Andromeda Galaxy. With a TV-85 at its native 600mm, you can capture the bright core, but the faint outer arms are often cropped. With the TRF-2008, the field expands to 480mm, perfectly framing the galaxy's full, majestic spiral structure. The faster f\/5.6 system also brings out the subtle details in the dust lanes with shorter sub-exposures, making the entire imaging process more productive and rewarding.\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\u003eChoosing the Right Tele Vue Corrector\u003c\/h3\u003e\n\u003cp\u003eTele Vue makes several correctors, and choosing the right one depends entirely on your telescope type and goals.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTRF-2008 0.8x Reducer:\u003c\/strong\u003e This is the correct choice for astrophotography with Tele Vue refractors having focal lengths between 400mm and 800mm. It provides both focal reduction and field flattening.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNPR-2073 0.8x Reducer:\u003c\/strong\u003e This reducer is designed specifically for the flat-field Nagler-Petzval optical design of the NP101is and NP127is telescopes. It will not properly flatten the field of a standard doublet refractor.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eParacorr Type 2:\u003c\/strong\u003e This is not a refractor accessory. The Paracorr is a coma corrector designed exclusively for correcting the optics of fast Newtonian reflectors. It is essential for imaging with Newtonians but is not compatible with refractors.\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 TRF-2008 work with my non-Tele Vue refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile it might seem to work, the TRF-2008 is optically optimized for the specific field curvature of Tele Vue refractors with focal lengths of 400-800mm. Using it on other brands may result in poor edge-of-field star shapes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat do I need to get the correct 56mm back focus spacing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA standard DSLR camera with a matching 10mm T-ring typically provides the correct 56mm spacing automatically. For dedicated astronomy cameras, you will need to check your camera's sensor depth and use M42 extension tubes to make up the difference.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the TRF-2008 for visual observing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, the TRF-2008 is designed exclusively for astrophotography. It does not have a provision for holding an eyepiece and will not reach focus for visual use.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is this reducer not recommended for the Tele Vue NP101is or NP127is?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe NP101is and NP127is telescopes have a built-in flattener (Petzval design) and a larger 2.4-inch focuser. The TRF-2008 would cause significant vignetting (darkening of the corners) on these scopes. They require the larger, dedicated NPR-2073 reducer.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the TRF-2008 correct for chromatic aberration?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, the reducer is not designed to correct for chromatic aberration (false color). That correction is the job of the telescope's main objective lens. The TRF-2008's purpose is to reduce the focal length and flatten 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\u003eProduct Code\u003c\/td\u003e\n\u003ctd\u003eTRF-2008\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType\u003c\/td\u003e\n\u003ctd\u003eFocal Reducer \/ Field Flattener\u003c\/td\u003e\n\u003c\/tr\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\u003eTelescope Connection\u003c\/td\u003e\n\u003ctd\u003e2-inch Barrel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Connection\u003c\/td\u003e\n\u003ctd\u003eMale M42x0.75 T-Thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired Back Focus\u003c\/td\u003e\n\u003ctd\u003e56mm ± 2mm from flange\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thread\u003c\/td\u003e\n\u003ctd\u003e48mm (for 2-inch filters)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e1.66\" (42mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e5.4 oz (153 g)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLength\u003c\/td\u003e\n\u003ctd\u003e1.8\" (46mm)\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\"\u003e0.8x Focal 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\"\u003eTop 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\"\u003eBottom 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\/Tele_Vue_0.8x_Focal_Reducer_Flattener_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\/tele-vue-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eTele Vue 5-Year Limited Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"TeleVue","offers":[{"title":"Default Title","offer_id":51223881154845,"sku":"TV-TRF-2008","price":403.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Tele_Vue_0.8x_Focal_Reducer_1.jpg?v=1777515015","url":"https:\/\/davidastro.com\/en-eu\/products\/tele-vue-0-8x-focal-reducer","provider":"David Astro","version":"1.0","type":"link"}