{"product_id":"zwo-90mm-quad-apo-refractor","title":"ZWO 90mm Quad APO Refractor","description":"\u003cp dir=\"ltr\"\u003e\u003cspan\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1979\/5379\/files\/FF90_10d7eaed-86a5-427a-9e2d-1d318ee3682f.jpg?v=1781064779\"\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eThe  FF90 APO's  609mm f\/6.8 optics cover a \u003cem\u003efull-frame, 44mm \u003c\/em\u003eimaging circle,\u003c\/span\u003e\u003cspan\u003e and \u003cem\u003ecan be used for both visual \u003c\/em\u003e\u003c\/span\u003e\u003cem\u003eobservation and astrophotography. \u003c\/em\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eThe telescope's\u003c\/span\u003e\u003cspan\u003e four-element design—including an ED element—means no more precisely calculating your backfocus—if you've got accurate focus, \u003cem\u003eyou'll get sharp stars out to the edges of your image.\u003c\/em\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eThis also means \u003cem\u003ethere's no need for a separate field flattene\u003c\/em\u003er—your stars will be sharp all the way to the \u003c\/span\u003ecorners, straight out of the box. \u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eThe FF90 APO OTA weighs o\u003cspan style=\"color: rgb(0, 0, 0);\"\u003enly 3.9 kg and the gross weight, including the tube rings and dovetail plate, is 4.5 kg—about 10 pounds.\u003c\/span\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eThe FF90 APO also comes standard with a photographic extension tube\u003c\/span\u003e\u003cspan\u003e, \u003c\/span\u003e\u003cspan\u003eincluding M48\u003c\/span\u003e\u003cspan\u003e*\u003c\/span\u003e\u003cspan\u003e0.75 and M54\u003c\/span\u003e\u003cspan\u003e*\u003c\/span\u003e\u003cspan\u003e0.75 adapters\u003c\/span\u003e\u003cspan\u003e, which work well with modern cameras. It also provides\u003c\/span\u003e\u003cspan\u003e a built-in \u003c\/span\u003e\u003cspan\u003e2\u003c\/span\u003e\u003cspan\u003e-inch \u003c\/span\u003e\u003cspan\u003efilter \u003c\/span\u003e\u003cspan\u003ethread inside the M48 adapter, in case you don't have a filter drawer yet\u003c\/span\u003e\u003cspan\u003e. \u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eThe handlebar of FF90 APO\u003c\/span\u003e\u003cspan\u003e \u003c\/span\u003e\u003cspan\u003edoubles guide scope mount, and\u003c\/span\u003e\u003cspan\u003e \u003c\/span\u003e\u003cspan\u003ethere are two additional \u003c\/span\u003e\u003cspan\u003efinder bases on both sides of the focuser, providing additional mounting positions for other astronomical accessories\u003c\/span\u003e\u003cspan\u003e.  (This is a great place to mount an ASI AIR!)\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eThe FF90 AP\u003cspan style=\"color: rgb(0, 0, 0);\"\u003eO boasts a rigid, dual-speed rack-and-pinion\u003c\/span\u003e\u003c\/span\u003e\u003cspan\u003e\u003cspan style=\"color: rgb(255, 42, 0);\"\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e focuser,\u003c\/span\u003e \u003c\/span\u003ewhich has a 1:10 fine adjustment and a 360° scale field rotator at the \u003c\/span\u003e\u003cspan\u003erear end for precise angle adjustment. \u003c\/span\u003e\u003cspan\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eThe FF90's retractable dew shield  further shortens the overall length and increases portability. The entire lens tube is crafted using high-quality CNC machining. The inside of the FF90 APO's dew shield is covered with matting paint to effectively reduce stray light reflections. \u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1979\/5379\/files\/90icon.jpg?v=1780981156\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e \u003c\/p\u003e\n\u003ch4\u003eMain Features\u003c\/h4\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1979\/5379\/files\/Highlights_1532c61a-0c40-4bf0-b877-f918d3f056bc.jpg?v=1781064996\"\u003e\u003c\/p\u003e\n\u003ch4\u003eUniqueness \u003cmeta charset=\"utf-8\"\u003e\n\u003c\/h4\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1979\/5379\/files\/Lightweight_Compact_645eaef4-6232-4235-8b3d-13328c6fe994.jpg?v=1781065154\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1979\/5379\/files\/Four-Element_Optical_Design.jpg?v=1781065222\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1979\/5379\/files\/Full-Frame_Support.jpg?v=1781065296\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1979\/5379\/files\/Clamp_12aeb99e-ea03-4789-bafd-0a3d847dd2f0.jpg?v=1781065402\"\u003e\u003c\/p\u003e\n\u003ch4\u003ePerformance\u003c\/h4\u003e\n\u003cp\u003e\u003cem\u003eStar Field Map\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1979\/5379\/files\/Bitmap_image_eeec432e-3678-4ed1-974d-a798627af484.jpg?v=1781065511\" alt=\"\"\u003e\u003c\/em\u003e\u003c\/p\u003e\n\u003ch4\u003eSpecifications \u003c\/h4\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/1979\/5379\/files\/Product_parameters.jpg?v=1781065721\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"ZWO","offers":[{"title":"Default Title","offer_id":48334265385219,"sku":"ZWO FF90-APO","price":999.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1979\/5379\/files\/FF90APO1_1296x_8d9f2cdd-fd6e-42ed-ac5b-7334e91e26a6.webp?v=1781122036","url":"https:\/\/milehighastro.com\/products\/zwo-90mm-quad-apo-refractor","provider":"Mile High Astronomy","version":"1.0","type":"link"}