{"product_id":"askar-sqa55-quintuplet-petzval-astrograph-55mm-f-4-8","title":"Askar SQA55 Quintuplet Petzval Astrograph 55mm f\/4.8","description":"\u003ch2\u003eAskar SQA55 Quintuplet Petzval Astrograph — 55mm f\/4.8\u003c\/h2\u003e\n\n\u003cp\u003eThe \u003cstrong\u003eAskar SQA55\u003c\/strong\u003e is a 55mm aperture, 264mm focal length, f\/4.8 quintuplet air-spaced Petzval astrograph designed for astrophotographers who demand sharp, flat full-frame star fields with the speed and portability to image anywhere. The optical design incorporates one piece of SD glass and one piece of ED glass to suppress chromatic aberration across the entire 44mm image circle, producing clean round stars from centre to corner on full-frame and APS-C sensors.\u003c\/p\u003e\n\n\u003cp\u003eAs a Petzval-design telescope, the SQA55 does not require a separate flattener — the five-element optical group delivers a flat field natively. A manual focus ring with an adjustable dew shield allows precise focus control in the field, and the 14-blade aperture diaphragm provides smooth out-of-focus backgrounds when the aperture is stopped down for daytime or landscape photography.\u003c\/p\u003e\n\n\u003cp\u003eThe SQA55 ships with a military-grade waterproof carrying case — one of the only astrographs in this aperture class to do so — making it a genuinely travel-ready system for remote dark-sky sites, star parties, and expeditions.\u003c\/p\u003e\n\n\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTravel and portable-mount astrophotographers\u003c\/strong\u003e who need a full-frame-capable astrograph in the smallest, lightest, most rugged package available.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eIntermediate to advanced astrophotographers\u003c\/strong\u003e who want a fast, high-quality Petzval design without adding a flattener to their imaging train.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWide-field deep-sky imagers\u003c\/strong\u003e targeting large nebulae, star clusters, and Milky Way fields that benefit from 264mm focal length and f\/4.8 speed.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDual-use photographers\u003c\/strong\u003e who also want a high-quality telephoto lens for landscape and daytime photography.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eImagers in light-polluted skies\u003c\/strong\u003e where the f\/4.8 speed dramatically shortens required exposure times.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhy Choose the Askar SQA55?\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQuintuplet Petzval with SD + ED glass\u003c\/strong\u003e — flat-field, colour-corrected performance across the full 44mm image circle at f\/4.8 with no external flattener required.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFast f\/4.8 focal ratio\u003c\/strong\u003e — collects light significantly faster than f\/6 or f\/7 instruments, cutting exposure times for faint nebulae and galaxies.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMilitary-grade waterproof case included\u003c\/strong\u003e — the only astrograph in this class that ships with expedition-grade protection.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003e14-blade aperture iris\u003c\/strong\u003e — adjustable from f\/4.8 to f\/22 for daytime photography with smooth, rounded bokeh.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDual-purpose design\u003c\/strong\u003e — usable as a high-quality telephoto lens for landscape, wildlife, and event photography.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFull-frame 44mm image circle\u003c\/strong\u003e — covers all modern full-frame DSLR, mirrorless, and dedicated astronomy cameras.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCompact and lightweight at 1.84kg OTA\u003c\/strong\u003e — compatible with ultralight tracking mounts for travel imaging.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQuick-release accessory system\u003c\/strong\u003e — four quick-release bases on the tube body accept the optional quick-release handle bar and accessories tool-free.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eWide-field deep-sky astrophotography (nebulae, star clusters, Milky Way)\u003c\/li\u003e\n  \u003cli\u003eNarrowband and broadband filter imaging from light-polluted sites\u003c\/li\u003e\n  \u003cli\u003eTravel and remote dark-sky imaging on ultralight mounts\u003c\/li\u003e\n  \u003cli\u003eFull-frame DSLR, mirrorless, and dedicated astronomy camera imaging\u003c\/li\u003e\n  \u003cli\u003eLandscape and telephoto photography (daytime use with aperture iris)\u003c\/li\u003e\n  \u003cli\u003ePortable guided and unguided wide-field imaging\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eCamera connection:\u003c\/strong\u003e M48×0.75 rear thread with built-in M48×0.75 2\" filter thread. Compatible with standard T-rings and M48 camera adapters. The recommended back focus connection distance is 55mm (range: 50–60mm). DSLR and mirrorless cameras connect via a T-ring; dedicated astronomy cameras with M48 nosepieces connect directly.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eFilter compatibility:\u003c\/strong\u003e M67 front thread (67mm screw-in filters); M48×0.75 rear thread accepts 2\" astronomy filters directly.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eOptional accessories:\u003c\/strong\u003e SQA55 Quick-Release Handle Bar, SQA55 AF Kit (electronic focuser adapter, sold separately).\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eNot compatible\u003c\/strong\u003e with the SQA Series Handle Bar or SQA Series Heightening Section — those accessories require a different mounting interface and are designed for the SQA70 and larger models.\u003c\/p\u003e\n\n\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManual focus only\u003c\/strong\u003e — the SQA55 does not have a motorized focuser. An electronic focuser requires the optional SQA55 AF Kit.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNot for visual observing\u003c\/strong\u003e — the SQA55 has no eyepiece holder or visual adapter. It is a dedicated photographic instrument.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003e55mm back focus must be respected\u003c\/strong\u003e — the specified 50–60mm back focus range is critical for field flatness. Spacers outside this range will degrade corner star quality.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eClosest focus distance 5m\u003c\/strong\u003e — the SQA55 cannot focus on subjects closer than 5 metres, limiting its terrestrial photography applications.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNo dovetail plate included\u003c\/strong\u003e — the SQA55 ships with the OTA, handle, and carrying case only. A dovetail plate or tube rings are required for mounting on a standard saddle.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eDo I need a flattener?\u003c\/strong\u003e\u003cbr\u003eNo. The quintuplet Petzval design provides a flat field natively across the full 44mm image circle at f\/4.8.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I use it for visual observing?\u003c\/strong\u003e\u003cbr\u003eNo. The SQA55 is a dedicated imaging instrument with no eyepiece holder.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the back focus?\u003c\/strong\u003e\u003cbr\u003e55mm recommended, with a usable range of 50–60mm from the base of the M48×0.75 male thread.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs a motorized focuser available?\u003c\/strong\u003e\u003cbr\u003eYes — the optional SQA55 AF Kit adapts virtually any brand of electronic focuser motor to the SQA55's focus ring, sold separately.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it work as a camera lens?\u003c\/strong\u003e\u003cbr\u003eYes, with the aperture iris set between f\/4.8 and f\/22. The closest focus distance is 5m, so it is best suited for landscape, astroscape, and distant subjects rather than close-up photography.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount do I need?\u003c\/strong\u003e\u003cbr\u003eAt 2.18kg gross, any equatorial tracking mount with at least a 4–6kg payload rating works well for imaging, including ultralight mounts like the ZWO AM5, iOptron HEM27, or Sky-Watcher Star Adventurer GTi.\u003c\/p\u003e\n\n\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\n\u003cp\u003eAt Ontario Telescope and Accessories, we recommend the \u003cstrong\u003eAskar SQA55\u003c\/strong\u003e for any astrophotographer who values portability without optical compromise. The f\/4.8 speed, flat-field Petzval design, and military-grade carrying case make it one of the most capable travel astrographs available at any price point. If you regularly image from remote locations, dark-sky parks, or travel internationally for astrophotography, the SQA55 delivers professional-grade results from a system that fits in carry-on luggage. For larger aperture or longer focal length, consider the SQA70 or SQA85.\u003c\/p\u003e\n\n\u003ch2\u003eOptical Diagram Reports\u003c\/h2\u003e\n\u003cp\u003eThe following diagrams are provided for customers who wish to review the mechanical dimensions, camera connection specifications, and electronic focuser assembly details for the Askar SQA55.\u003c\/p\u003e\n\u003cimg src=\"https:\/\/omo-oss-image1.thefastimg.com\/portal-saas\/pg2024111409483993253\/cms\/image\/ad04c525-150e-432d-9d40-029448807e34.jpg?vf=B7gH3s\" alt=\"Askar SQA55 Product Size Diagram - tube and dew shield dimensions\" style=\"max-width:100%;display:block;margin:1em 0;\"\u003e\n\u003cimg src=\"https:\/\/omo-oss-image1.thefastimg.com\/portal-saas\/pg2024111409483993253\/cms\/image\/1e3ab7f8-e65b-4607-83e8-a7797fbe3809.jpg?vf=B7gH3s\" alt=\"Askar SQA55 Connection Diagram - M48 rear adapter and camera connection details\" style=\"max-width:100%;display:block;margin:1em 0;\"\u003e\n\u003cimg src=\"https:\/\/omo-oss-image1.thefastimg.com\/portal-saas\/pg2024111409483993253\/cms\/image\/6e54949f-2222-49c1-97bf-44f8e520df8a.jpg?vf=B7gH3s\" alt=\"Askar SQA55 AF Kit Assembly Diagram - electronic focuser motor installation on SQA55 focus ring\" style=\"max-width:100%;display:block;margin:1em 0;\"\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":53154403614831,"sku":"SQA55-PETZVAL","price":1113.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/855d05fd-bdbb-47f2-ab27-4f90b22a2dd3.png?v=1779668681","url":"https:\/\/ontariotelescope.com\/products\/askar-sqa55-quintuplet-petzval-astrograph-55mm-f-4-8","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}