{"product_id":"askar-f-3-9-full-frame-reducer-for-fra400c-rfra400c","title":"Askar F\/3.9 Full Frame Reducer for FRA400C (RFRA400C)","description":"\u003cp\u003eSpecially designed for the FRA400C, this 0.7x reducer adopts a triplet lens design, it can reduce the overall focal length to 280mm and the focal ratio to F\/3.9 while providing a flat-field correction. When used with the reducer, the FRA400C supports full-frame imaging and the back focus is a standard 55mm.\u003c\/p\u003e\n\u003cp\u003eThe shorter focal ratio enables the telescope to achieve a wider field of view and faster exposure times, making it ideal for capturing large nebulae, star clusters, as well as faint and fast-moving celestial objects.\u003c\/p\u003e\n\u003cp\u003eThe FRA400C reducer features an M48×0.75 rear-end adapter and has a built-in 2-inch filter thread for convenient filter attachment.\u003c\/p\u003e\n\u003ch4\u003eInstallation Instructions\u003c\/h4\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0610\/7702\/9116\/files\/RFRA400C-INSTALLATION-STEP-1.jpg?v=1746992266\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0610\/7702\/9116\/files\/RFRA400C-INSTALLATION-STEP-2.jpg?v=1746992266\" alt=\"\"\u003e\u003c\/p\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e(After attaching) FRA400C Focal length\u003c\/td\u003e\n\u003ctd\u003e280mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e(After attaching) FRA400C Focal ratio\u003c\/td\u003e\n\u003ctd\u003ef\/3.9\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLens Number\u003c\/td\u003e\n\u003ctd\u003eTriplet design\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\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.46kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear-end thread type\u003c\/td\u003e\n\u003ctd\u003eM48×0.75 (M48×0.75 filter thread inside)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0610\/7702\/9116\/files\/RFRA400C-SIZE-DIAGRAM.jpg?v=1746992266\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eSPOT Diagram\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0610\/7702\/9116\/files\/RFRA400C-SPOT.jpg?v=1746992125\" alt=\"\"\u003e\u003c\/p\u003e","brand":"SharpStar","offers":[{"title":"Default Title","offer_id":47148151767292,"sku":"RFRA400C","price":348.6,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0610\/7702\/9116\/files\/RFRA400C-1.png?v=1746991957","url":"https:\/\/all-startelescope.com\/fr\/products\/askar-f-3-9-full-frame-reducer-for-fra400c-rfra400c","provider":"All-Star Telescope Canada","version":"1.0","type":"link"}