{"product_id":"askar-131f-131-mm-f-7-5-quadruplet-flat-field-apo-refractor-131f","title":"Askar 131F - 131 mm f\/7.5 Quadruplet Flat-Field APO Refractor - 131F","description":"\u003cdiv class=\"card__header\"\u003e\n\u003ch3 style=\"text-align: center;\" class=\"card__title heading h3\"\u003eAskar 131 mm Quad ED APO Flat-Field Refractor\u003c\/h3\u003e\n\u003cdiv style=\"text-align: center;\" class=\"card__title heading h3\"\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(255, 42, 0);\"\u003eBoy, we sold out fast!  Pre-Order now for the 2nd shipment!\u003c\/span\u003e\u003c\/strong\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\" class=\"card__title heading h3\"\u003e\n\u003cstrong\u003e\u003cspan style=\"color: rgb(255, 42, 0);\"\u003e\u003c\/span\u003e\u003c\/strong\u003e\u003cbr\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\" class=\"card__title heading h3\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/files\/131F_Hero.jpg?v=1778788114\" alt=\"\"\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch3 style=\"text-align: center;\"\u003eAskar 131F Flat Field Quad Refractor Highlights\u003c\/h3\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/files\/131F_Highlight_Icons.png?v=1778788688\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003eThe Askar 131F is a telescope OTA with an aperture of 131mm, a focal length of 983mm, and a native focal ratio of F\/7.5. It is designed for both visual observation and astrophotography.\u003c\/p\u003e\n\u003cp\u003eThe quadruplet lens system—comprising three front elements and one rear element, including one piece of ED glass—effectively minimizes chromatic aberration and supports 44mm full-frame imaging. \u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/files\/131_Full_Frame.jpg?v=1778788986\"\u003e\u003c\/p\u003e\n\u003cp\u003eThis 131 mm Quadruplet Refractor has a self-flattened design that allows users to avoid calculating the back focus and buying an additional flattener.  After attaching the imaging accessories, users can use it for photography after the OTA is in focus. This further reduces the cost and improves the pleasure imaging through your 131F.\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eAdhering to Askar's consistent design philosophy, the Askar 131F emphasizes detail and user experience, striving to reduce the cost of use. The lens hood is retractable, further shortening the overall length and enhancing portability. The lens tube utilizes high-quality CNC machining and painting processes. Its appearance continues the F-series' classic blue and white color scheme, presenting a simple and elegant aesthetic.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe Askar 131F comes standard with a photographic extension tube, which is designed with a 2-inch filter thread. It includes adapters with M48*0.75 and M54*0.75 specifications, ensuring compatibility with DSLR cameras or astronomy cameras to meet diverse needs.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe Askar 111F is equipped with a 3-inch rack-and-pinion dual-speed focuser supporting 1:10 fine adjustment. The fine adjustment knob includes a protective cap to prevent damage. The rear of the focuser connects to a 360° graduated rotator, allowing for precise angle adjustments.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/files\/131F_Accessory_Panels.jpg?v=1778789530\"\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: left;\"\u003e\u003cspan\u003eThe handle of the Askar 131F is equipped with a finder base slot. Additionally, both sides of the focuser feature finder bases. This not only allows for changing the finder scope position without disassembly but also provides more locations for installing other astronomical accessories.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: left;\"\u003e\u003cspan\u003eThe 300 mm Losmandy dovetail plate of the Askar 131F is compatible with most equatorial mounts and bases on the market.  The dovetail plate is designed with multiple holes, which makes it easy to adjust the position.  The entire plate is manufactured using high-quality CNC machining.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/files\/131F_with_Designations.jpg?v=1778789794\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/files\/131F_WITB.jpg?v=1778789830\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/files\/131F_Reducer_Main.webp?v=1778790264\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003eThe optional 0.74x reducer, shown above, brings the Askar 131F's focal ratio down to F\/5.6.  This reducer features a triplet optical design and supports a 44mm full-frame image circle.\u003c\/p\u003e\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003ctable class=\"ck-table-resized\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eAperture size\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\u003cstrong\u003e131mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eFocal length\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\u003cstrong\u003e983mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eFocal ratio\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\u003cstrong\u003ef\/7.5\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eObjective lens\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\u003cstrong\u003eQuadruplet air-spaced APO(including one ED glass)\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eImage circle\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\u003cstrong\u003e44mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMaximum accessory connection (with the focuser fully retreated)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003eImaging mode: \u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e73mm (from the base of M48×0.75 male thread）\u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e91mm（from the base of M54×0.75 male thread)\u003c\/strong\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003eObserving mode:  \u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e131mm（from the end of 1.25\" eyepiece holder）\u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e141mm（from the end of 2\" eyepiece holder）\u003c\/strong\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMinimum accessory connection (with the focuser fully extended)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003eImaging mode: \u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e43mm (from the base of M48×0.75 male thread）\u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e61mm（from the base of M54×0.75 male thread)\u003c\/strong\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003eObserving mode:  \u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e101mm（from the end of 1.25\" eyepiece holder）\u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e111mm（from the end of 2\" eyepiece holder）\u003c\/strong\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTotal length\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\n\u003cstrong\u003e878mm(including 1.25\" adapter as dew shield contracted）\u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e963mm(including 1.25\" adapter as dew shield fully stretched）\u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e941mm(including the photographic adapter as dew shield contracted）\u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e1026mm(including the photographic adapter as dew shield fully stretched）\u003c\/strong\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eFocuser travel length\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\u003cstrong\u003e30mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eNet weight\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\u003cstrong\u003e7.9kg\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eGross weight (Including tube ring\u0026amp;dovetail plate)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\u003cstrong\u003e9.4kg\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eRear-end thread type\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\n\u003cstrong\u003eM78×1-M54×0.75        \u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003eM54×0.75-M54×0.75        \u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003eM54×0.75-M48×0.75  (with M48×0.75 filter thread)\u003c\/strong\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eStandard package items\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\"\u003e\u003cstrong\u003e A 131F OTA, a pair of tube rings, a handle, a 300mm Losmandy dovetail plate, a set of photographic adapters\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cdiv class=\"reset_style\" id=\"ie_text-1707197718594\"\u003e\u003c\/div\u003e\n\u003cdiv class=\"cbox-15 p_loopItem\" id=\"saf-detail-1\"\u003e\n\u003cdiv class=\"e_richText-17 s_title clearfix response-transition\"\u003e\n\u003cp style=\"text-align: center;\"\u003e \u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":43243464163441,"sku":"ASK-131F","price":2799.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/files\/131F_Front_Right.webp?v=1778790377","url":"https:\/\/khanscope.com\/products\/askar-131f-131-mm-f-7-5-quadruplet-flat-field-apo-refractor-131f","provider":"Khan Scope Centre","version":"1.0","type":"link"}