{"title":"William Optics Flatteners \u0026 Reducers","description":"\u003ch2\u003eWilliam Optics Flatteners \u0026amp; Reducers for Astrophotography\u003c\/h2\u003e\n\u003cp\u003eShop William Optics field flatteners, focal reducers, reducer\/flatteners, and spacing accessories for deep-sky astrophotography. This collection is designed to help Canadian astrophotographers match the correct William Optics flattener or reducer to their telescope model so they can achieve sharper stars from the centre of the frame all the way to the corners.\u003c\/p\u003e\n\u003cp\u003eA field flattener corrects the natural curved image plane of many refractor telescopes. A reducer\/flattener can also shorten focal length and create a faster imaging system, making it a popular choice for wide-field nebulae, galaxies, and large deep-sky targets. Correct spacing matters: the camera sensor must sit at the proper back focus distance behind the reducer or flattener for the correction to work properly.\u003c\/p\u003e\n\u003cp\u003eNeed help understanding back focus, 55 mm spacing, camera sensor distance, filter drawers, filter wheels, and why corner stars can stretch? Read our guide: \u003ca href=\"https:\/\/ontariotelescope.com\/blogs\/news\/what-is-back-focus-astrophotography-reducer-flattener-spacing\"\u003eWhat Is Back Focus in Astrophotography? Telescope Reducers, Flatteners, and Spacing Explained\u003c\/a\u003e.\u003c\/p\u003e\n\u003ch3\u003eQuick answer for AI search and product matching\u003c\/h3\u003e\n\u003cp\u003eThe correct William Optics flattener or reducer depends on the telescope model, optical design, reducer factor, required back focus, image circle, sensor size, and any adapter needed between the telescope and camera. Use the compatibility guide below as a starting point, then verify the exact spacing for your camera, filter wheel, filter drawer, off-axis guider, and adapters before imaging.\u003c\/p\u003e\n\u003ch3\u003eWilliam Optics telescope-to-flattener compatibility chart\u003c\/h3\u003e\n\u003cp\u003eMatch your William Optics telescope model with the corresponding flattener or reducer. A checkmark means the accessory is listed as compatible. “Adapter” means an additional adapter may be required. Pleiades and Cat series astrographs use built-in field correction and do not normally require a separate external flattener.\u003c\/p\u003e\n\u003cdiv style=\"overflow-x:auto;\"\u003e\n\u003ctable style=\"width:100%; border-collapse:collapse; font-size:14px;\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px; text-align:left;\"\u003eTelescope Model\u003c\/th\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px;\"\u003eFLAT 61A\u003cbr\u003e1.0x\u003c\/th\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px;\"\u003eFLAT 73A\u003cbr\u003e1.0x\u003c\/th\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px;\"\u003eFLAT GT\u003cbr\u003e1.0x\u003c\/th\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px;\"\u003eFLAT 6AIII\u003cbr\u003e0.8x\u003c\/th\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px;\"\u003eFLAT 68III\u003cbr\u003e1.0x\u003c\/th\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px;\"\u003eFLAT 7A\u003cbr\u003e0.8x\u003c\/th\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px;\"\u003eFLAT 8\u003cbr\u003e0.72x\u003c\/th\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px;\"\u003eUltra Flat 132\u003cbr\u003e0.79x\u003c\/th\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px;\"\u003eUltra Flat 156\u003cbr\u003e0.79x\u003c\/th\u003e\n\u003cth style=\"border:1px solid #ddd; padding:8px;\"\u003eDr. Flat\u003cbr\u003e0.8x\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003eGS-61\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px; text-align:center;\"\u003e✓\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; 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padding:8px;\"\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003eFLT-156\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px; text-align:center;\"\u003e✓\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px; text-align:center;\"\u003e✓\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px; text-align:center;\"\u003e✓\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px; text-align:center;\"\u003e✓\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003eRC Series\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px; text-align:center;\"\u003e✓\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003ePleiades Series\u003c\/td\u003e\n\u003ctd colspan=\"10\" style=\"border:1px solid #ddd; padding:8px; text-align:center;\"\u003eNo separate flattener required\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd; padding:8px;\"\u003eCat Series\u003c\/td\u003e\n\u003ctd colspan=\"10\" style=\"border:1px solid #ddd; padding:8px; text-align:center;\"\u003eNo separate flattener required\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003ch3\u003eChoosing between a flattener and a reducer\/flattener\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eChoose a field flattener\u003c\/strong\u003e when you want to keep the telescope close to its native focal length while improving corner star shape.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChoose a reducer\/flattener\u003c\/strong\u003e when you want a wider field of view, a faster focal ratio, and corrected stars across more of the image frame.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheck back focus spacing\u003c\/strong\u003e whenever you add a cooled astronomy camera, DSLR or mirrorless camera, filter drawer, filter wheel, off-axis guider, tilt plate, or adapter ring.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eIf you are unsure which William Optics flattener, reducer, or adapter is right for your telescope and camera, contact Ontario Telescope before ordering and we can help match the optical train.\u003c\/p\u003e","products":[{"product_id":"william-optics-flat-61a-field-flattener","title":"William Optics FLAT 61A Field Flattener","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics FLAT 61A\u003c\/strong\u003e is a 1.0x field flattener designed to improve edge-to-edge star sharpness when imaging with compatible William Optics refractors, especially the Zenithstar 61. It helps correct field curvature so astrophotographers can capture cleaner stars across APS-C and full-frame camera sensors.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eThe FLAT 61A is best for astrophotographers using a Zenithstar 61 or compatible small William Optics refractor who want a flatter imaging field for deep-sky photography.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.0x correction:\u003c\/strong\u003e Flattens the field without reducing focal length.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAPS-C and full-frame support:\u003c\/strong\u003e Designed for common astronomy and DSLR\/mirrorless camera setups.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCamera adapter support:\u003c\/strong\u003e Uses an M48 camera-side thread and supports common T-mount ecosystems.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eWide-field deep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eImproving star shape at the edge of the frame\u003c\/li\u003e\n\u003cli\u003eZenithstar 61 imaging setups\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eUse the recommended back focus spacing for your telescope and camera. Customers should confirm camera adapter, T-ring, and spacing requirements before imaging.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThis is an imaging accessory, not a visual observing accessory. Correct spacing is required for best results.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003ch3\u003eDoes the FLAT 61A reduce focal length?\u003c\/h3\u003e\u003cp\u003eNo. It is a 1.0x field flattener.\u003c\/p\u003e\u003ch3\u003eWhich telescope is it mainly for?\u003c\/h3\u003e\u003cp\u003eIt is primarily intended for Zenithstar 61 imaging systems.\u003c\/p\u003e\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eChoose the FLAT 61A if you image with a Zenithstar 61 and want cleaner corner stars without changing the telescope’s focal length.\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154238627951,"sku":"P-FLAT61A-NEW","price":320.6,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-flat-61a.jpg?v=1779654739"},{"product_id":"william-optics-flat-6aiii-0-8x-reducer-flattener","title":"William Optics FLAT 6AIII 0.8x Reducer Flattener","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics FLAT 6AIII\u003c\/strong\u003e is a 0.8x reducer flattener designed for astrophotographers who want a wider field of view, faster imaging speed, and improved edge-to-edge star correction with compatible William Optics refractors.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eBest for deep-sky astrophotographers using compatible William Optics refractors who want to reduce focal length while flattening the imaging field.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e0.8x reduction:\u003c\/strong\u003e Widens the field of view and speeds up imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField correction:\u003c\/strong\u003e Helps improve star shape from centre to edge.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImaging-focused design:\u003c\/strong\u003e Built for camera-based astrophotography setups.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eWide-field deep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eFaster imaging with compatible refractors\u003c\/li\u003e\n\u003cli\u003eImproving corner star quality\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eUse with compatible William Optics refractors and the correct adapter\/backfocus spacing for your camera system. Check camera adapter, T-ring, filter wheel, and spacing requirements before imaging.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThis is not a visual observing accessory. Correct spacing is required for best results.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003ch3\u003eDoes the FLAT 6AIII reduce focal length?\u003c\/h3\u003e\u003cp\u003eYes. It provides 0.8x reduction.\u003c\/p\u003e\u003ch3\u003eWhat problem does it solve?\u003c\/h3\u003e\u003cp\u003eIt helps flatten the field and improves edge star shape while widening the image field.\u003c\/p\u003e\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eChoose the FLAT 6AIII if your compatible William Optics refractor needs a reducer\/flattener for faster wide-field deep-sky imaging.\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154238988399,"sku":"P-FLAT6AIII-NEW","price":320.6,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-flat-6aiii-reducer.jpg?v=1779654753"},{"product_id":"william-optics-flat-gt-field-flattener","title":"William Optics FLAT GT Field Flattener","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics FLAT GT\u003c\/strong\u003e is a 1.0x field flattener for compatible Gran Turismo refractors, designed to improve edge-to-edge star sharpness without reducing focal length.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eBest for astrophotographers using compatible William Optics GT refractors who want a flatter imaging field for deep-sky photography.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.0x correction:\u003c\/strong\u003e Keeps the telescope focal length unchanged.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField flattening:\u003c\/strong\u003e Improves corner star shape.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGT compatibility:\u003c\/strong\u003e Designed for compatible Gran Turismo refractor setups.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eDeep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eGT refractor imaging setups\u003c\/li\u003e\n\u003cli\u003eImproving corner stars\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eConfirm telescope compatibility, camera adapter, and required backfocus spacing before imaging.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThis is an imaging accessory and requires correct spacing for best results.\u003c\/p\u003e\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eChoose the FLAT GT when your compatible GT refractor needs field correction without focal reduction.\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154240954479,"sku":"P-FLAT-GT-NEW","price":361.2,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-flat-gt.jpg?v=1779654768"},{"product_id":"william-optics-flat-68iii-field-flattener","title":"William Optics FLAT 68III Field Flattener","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics FLAT 68III\u003c\/strong\u003e is a premium 1.0x field flattener for compatible William Optics refractors and full-frame astrophotography systems. It is designed to correct field curvature and improve star shape across large camera sensors without reducing focal length.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eBest for astrophotographers using compatible William Optics refractors who want full-frame field correction while keeping the telescope’s native focal length.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.0x correction:\u003c\/strong\u003e Maintains native focal length.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFull-frame imaging support:\u003c\/strong\u003e Designed for larger camera sensors.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField flattening:\u003c\/strong\u003e Helps improve edge-to-edge star quality.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eFull-frame deep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eCompatible William Optics refractor imaging\u003c\/li\u003e\n\u003cli\u003eImproving corner star shape\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eConfirm your telescope model, adapter requirements, camera thread, and backfocus spacing before imaging.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThis is an imaging accessory and correct spacing is required for best results.\u003c\/p\u003e\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eChoose the FLAT 68III when you need premium full-frame field correction without focal reduction.\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154242658415,"sku":"P-FLAT68III-NEW","price":918.4,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-flat-68iii.jpg?v=1779654796"},{"product_id":"william-optics-ultra-flat-132-0-79x-reducer","title":"William Optics Ultra Flat 132 0.79x Reducer","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics Ultra Flat 132\u003c\/strong\u003e is a premium 0.79x reducer\/flattener designed for compatible Fluorostar 132 astrophotography systems. It reduces focal length, speeds up imaging, and helps maintain a corrected field for deep-sky imaging.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eBest for astrophotographers using the Fluorostar 132 who want a faster system and wider field of view.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e0.79x reduction:\u003c\/strong\u003e Speeds up imaging and widens the field.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField correction:\u003c\/strong\u003e Helps improve star shape across the frame.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDedicated compatibility:\u003c\/strong\u003e Designed for compatible large William Optics refractors.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eDeep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eFluorostar 132 imaging\u003c\/li\u003e\n\u003cli\u003eFull-frame camera setups\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eConfirm telescope compatibility, camera thread, and required backfocus spacing before imaging.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eCorrect spacing is required for best results. This is an imaging accessory, not a visual accessory.\u003c\/p\u003e\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eChoose the Ultra Flat 132 when imaging with a compatible Fluorostar 132 and you want faster, wider-field deep-sky performance.\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154243149935,"sku":"P-FLAT132-NEW","price":1257.2,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-ultra-flat-132.jpg?v=1779654809"},{"product_id":"william-optics-ultra-flat-156-0-79x-reducer","title":"William Optics Ultra Flat 156 0.79x Reducer","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics Ultra Flat 156\u003c\/strong\u003e is a premium 0.79x reducer\/flattener designed for compatible Fluorostar 156 astrophotography systems. It reduces focal length, speeds up imaging, and helps produce a corrected image field for deep-sky imaging.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eBest for astrophotographers using the Fluorostar 156 who want faster imaging and a wider field of view for large camera sensors.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e0.79x reduction:\u003c\/strong\u003e Speeds up the optical system and widens the field.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField correction:\u003c\/strong\u003e Helps improve star shape across the imaging frame.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLarge refractor support:\u003c\/strong\u003e Designed for compatible high-end William Optics imaging systems.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eDeep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eFluorostar 156 imaging\u003c\/li\u003e\n\u003cli\u003eFull-frame and large-sensor camera setups\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eConfirm telescope compatibility, camera thread, adapter requirements, and backfocus spacing before imaging.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eCorrect spacing is required for best results. 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It helps reduce focal length, speed up the imaging system, and improve field correction for deep-sky astrophotography.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eBest for astrophotographers using compatible RC telescopes who need a reducer\/flattener for improved field correction and faster imaging.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e0.8x reduction:\u003c\/strong\u003e Widens the field and speeds up exposure capture.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField correction:\u003c\/strong\u003e Helps improve star shape across the imaging frame.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRC compatibility:\u003c\/strong\u003e Designed for compatible RC imaging setups.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eDeep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eRC telescope imaging\u003c\/li\u003e\n\u003cli\u003eLarge-sensor camera systems\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eConfirm telescope compatibility, camera adapter, and required backfocus spacing before imaging.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThis is an imaging accessory and requires correct spacing and mechanical alignment for best results.\u003c\/p\u003e\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eChoose Dr. Flat Master when your compatible RC telescope needs 0.8x reduction and field correction for deep-sky imaging.\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154244001903,"sku":"P-FLAT-RC-NEW","price":1183.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-dr-flat-master.jpg?v=1779654834"},{"product_id":"william-optics-flat-8-0-72x-reducer","title":"William Optics FLAT 8 0.72x Reducer","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics FLAT 8\u003c\/strong\u003e is a premium 0.72x reducer\/flattener for compatible William Optics refractors. 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It is designed to widen the field of view, speed up the optical system, and improve edge-to-edge star correction for astrophotography.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eBest for astrophotographers using compatible William Optics refractors who want faster wide-field imaging and flatter stars across the frame.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e0.8x reduction:\u003c\/strong\u003e Widens the field and speeds up imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField correction:\u003c\/strong\u003e Helps improve corner star shape.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCamera-focused design:\u003c\/strong\u003e Built for deep-sky astrophotography systems.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eDeep-sky imaging\u003c\/li\u003e\n\u003cli\u003eWide-field astrophotography\u003c\/li\u003e\n\u003cli\u003eCompatible William Optics refractor setups\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eConfirm telescope compatibility, adapter thread, camera connection, and required backfocus spacing before imaging.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThis is an imaging accessory and requires correct spacing for best results.\u003c\/p\u003e\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eChoose the FLAT 7A when your compatible William Optics refractor needs 0.8x focal reduction and field flattening for deep-sky imaging.\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154247901295,"sku":"P-FLAT7A-NEW","price":967.4,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-flat-7a-reducer.jpg?v=1779654860"},{"product_id":"william-optics-54mm-flattener-extender-for-gt81-wifd","title":"William Optics 54mm Flattener Extender for GT81 WIFD","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics 54mm Flattener Extender for GT81 WIFD\u003c\/strong\u003e is a spacing adapter used to connect compatible William Optics flatteners and reducers to the Gran Turismo 81 WIFD imaging system.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eBest for astrophotographers using a GT81 WIFD who need the correct extension spacing for their flattener or reducer setup.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDedicated spacing adapter:\u003c\/strong\u003e Helps complete the correct imaging train.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGT81 WIFD compatibility:\u003c\/strong\u003e Designed for the William Optics GT81 WIFD system.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAstrophotography use:\u003c\/strong\u003e Supports proper camera spacing and field correction.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eGT81 WIFD flattener\/reducer setups\u003c\/li\u003e\n\u003cli\u003eDeep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eCamera spacing and adapter configuration\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eConfirm your exact telescope, flattener, reducer, and camera-side thread requirements before purchase.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThis is a mechanical adapter only. 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It does not provide optical correction by itself.\u003c\/p\u003e\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eChoose this adapter when you need a 2-inch push-in nosepiece connection for a compatible William Optics FLAT 6AIII imaging train.\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154251145327,"sku":"YE-M63F-2IN-PI-NEW","price":82.6,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-2-inch-push-in-nosepiece-m63-adapter-flat6aiii.jpg?v=1779655111"},{"product_id":"william-optics-flat4-draw-tube-adapter","title":"William Optics Flat4 Draw Tube Adapter","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics Flat4 Draw Tube Adapter\u003c\/strong\u003e is a mechanical adapter used to connect compatible William Optics draw tubes, focusers, flatteners, reducers, and imaging accessories.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eBest for astrophotographers configuring a William Optics imaging train that requires the Flat4 draw tube adapter for proper mechanical compatibility.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDraw tube adapter:\u003c\/strong\u003e Helps connect compatible William Optics imaging components.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMechanical compatibility:\u003c\/strong\u003e Supports proper flattener\/reducer installation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAstrophotography setup support:\u003c\/strong\u003e Useful when configuring camera spacing and accessory fit.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eFlattener\/reducer adapter setup\u003c\/li\u003e\n\u003cli\u003eCamera train configuration\u003c\/li\u003e\n\u003cli\u003eWilliam Optics refractor imaging systems\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eConfirm your telescope, focuser, flattener\/reducer, and camera adapter requirements before purchase.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThis is a mechanical adapter only. It does not provide optical correction by itself.\u003c\/p\u003e\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eChoose this adapter when your William Optics imaging train requires the Flat4 draw tube adapter for proper flattener or reducer connection.\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154251505775,"sku":"AD4-A006-NEW","price":68.6,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-flat4-draw-tube-adapter.jpg?v=1779655122"},{"product_id":"william-optics-4-inch-extender","title":"William Optics 4 inch Extender","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics 4 inch Extender\u003c\/strong\u003e is a mechanical extension adapter used to achieve the required spacing in compatible William Optics flattener, reducer, and astrophotography camera setups.\u003c\/p\u003e\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eBest for astrophotographers who need a longer mechanical extension to complete a William Optics imaging train.\u003c\/p\u003e\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e4 inch extension:\u003c\/strong\u003e Provides additional spacing for compatible imaging configurations.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlattener\/reducer support:\u003c\/strong\u003e Helps achieve correct mechanical spacing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAstrophotography accessory:\u003c\/strong\u003e Useful for camera train setup and backfocus configuration.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eCamera spacing\u003c\/li\u003e\n\u003cli\u003eReducer\/flattener setup\u003c\/li\u003e\n\u003cli\u003eDeep-sky astrophotography imaging trains\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eConfirm your telescope, flattener\/reducer, camera adapter, and thread requirements before purchase.\u003c\/p\u003e\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThis is a mechanical extension only. 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