{"product_id":"askar-0-74x-131f-reducer-askar131fr","title":"Askar 0.74x 131F Reducer | ASKAR131FR","description":"\u003cp\u003eDesigned exclusively for the Askar 131F, this 0.74× reducer reduces the 131F focal ratio to F5.6, unlocking more potential for your imaging possibilities.\u003c\/p\u003e\n\u003cp\u003eThis 0.74× Reducer is the ideal companion for the Askar 131F telescope, reducing the focal ratio from f\/7.5 to f\/5.6. This dramatically shortens exposure times, allowing you to effortlessly capture wide-field nebulae, dense star clusters, as well as faint or fast-moving celestial objects.\u003c\/p\u003e\n\u003cp\u003eIt also incorporates field-flattening correction capabilities, effectively eliminating field curvature to ensure sharp, clear stars from the center to the edges of the frame.\u003c\/p\u003e\n\u003cp\u003eFeaturing a triplet optical lens design, this reducer supports a 44mm full-frame image circle. It has a standard back focus of 55mm (measured from the M48 thread), with M72×1 threads on both ends. The package includes an extension tube and comes with both M54×0.75 and M48×0.75 adapter rings that connect directly to the reducer for easy installation. The rear adapter ring features a built-in M48×0.75 thread, enabling direct attachment of 2-inch filters.\u003c\/p\u003e\n\u003cp\u003eConstructed using CNC machining, the reducer is equipped with metal thread caps on both ends. These caps protect the optics and offer convenient dust-proof storage, reflecting the product's professional quality.\u003c\/p\u003e\n\u003ch2\u003eSpecifications\u003cbr\u003e\n\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"2\"\u003e\u003cstrong\u003eParameter\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e （After attaching）60F Focal length\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003e733.6mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e （After attaching）60F Focal ratio\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003ef\/5.6\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLens Number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eTriplet design\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eBack Focus\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003e55mm（from the base of M48 male thread）\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eWeight\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003e0.56kg\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\u003e\u003cstrong\u003eM72*1\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003eSize Diagram\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0610\/7702\/9116\/files\/b8ba6641-f768-4a50-a30e-137d3bb2aaf4.webp?v=1778277465\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003eInstallation\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0610\/7702\/9116\/files\/f2814497-8813-43b5-9b6a-71f9c3ab355b.webp?v=1778277466\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003eOptical Path Diagram\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0610\/7702\/9116\/files\/7e3a109f-9f5f-4b08-b223-f4823567ab21.webp?v=1778277465\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003eSpot Diagram\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0610\/7702\/9116\/files\/7b275b64-0102-442f-87cf-fa1816ab032f.webp?v=1778277465\" alt=\"\"\u003e\u003c\/p\u003e","brand":"SharpStar","offers":[{"title":"Default Title","offer_id":49079576396028,"sku":"ASKAR131FR","price":294.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0610\/7702\/9116\/files\/774a6f79-0b33-498c-97ea-43af4c9ff1f5.webp?v=1778277549","url":"https:\/\/usa.all-startelescope.com\/products\/askar-0-74x-131f-reducer-askar131fr","provider":"All-Star Telescope Canada","version":"1.0","type":"link"}