{"title":"Astrographes à champ plat Askar F","description":"\u003cp\u003eLes Askar F sont des lunettes apochromatiques à champ plat conçues pour l'astrophotographie sans aplanisseur séparé. La gamme va de la compacte 60F et de la 71F quadruplet à f\/6.9 jusqu'aux 91F, 111F et 131F, pour choisir une focale adaptée aux grands champs de nébuleuses ou aux galaxies plus petites.\u003c\/p\u003e\u003cp\u003eChaque modèle a son réducteur de focale dédié, 0.75x pour les 60F, 71F et 91F et 0.74x pour les 111F et 131F, pour un rapport focal plus rapide et un champ plus large au besoin.\u003c\/p\u003e","products":[{"product_id":"askar-71f-quadruplet-flat-field-apo-f-6-9","title":"Askar 71F Quadruplet champ plat APO f\/6.9","description":"\u003cul\u003e\n\n\u003cli\u003e\n\n Ouverture de 71 mm, réfracteur apochromatique quadruplet à rapport focal f\/6,9\n\n\u003c\/li\u003e\n\n\u003cli\u003e\n\n Conception à champ plat optimisée pour l'astrophotographie à grand champ \n\n\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\n\u003cli class=\"active\"\u003e Description \u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\n\n\u003cul class=\"tabs-content\"\u003e\n\n\u003cli class=\"active\"\u003e\n\n\u003cp\u003e \nL'Askar 71F Quadruplet Flat-Field APO f\/6.9 est un télescope réfracteur apochromatique haute performance spécialement conçu pour l'astrophotographie à grand champ. Avec son ouverture de 71 mm et son rapport focal rapide de f\/6,9, ce télescope offre un excellent équilibre entre puissance de collecte de lumière et champ de vision, ce qui le rend idéal pour capturer de vastes objets du ciel profond et des champs d'étoiles. \n\u003c\/p\u003e\n\n\u003cdiv class=\"warning\"\u003e\n\n\u003cimg alt=\"Clause de non-responsabilité\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/warning-logo.svg?v=1714663206\" width=\"25px\"\u003e\n\u003cp\u003e\n Optimisé pour l'astrophotographie. Des accessoires supplémentaires peuvent être nécessaires pour une utilisation visuelle. Vérifiez la compatibilité avec votre équipement d’imagerie existant.\n\u003c\/p\u003e\n\n\n\u003c\/div\u003e\n\n\n\u003cdiv\u003e\n\n\u003ch3\u003e\n\n Conception optique \n\n\u003c\/h3\u003e\n\n\u003chr\u003e\n\n\u003cdiv class=\"two-columns-section\"\u003e\n\n\u003cdiv class=\"text-side-2\"\u003e\n\n\u003cp\u003e\n Le 71F présente une conception sophistiquée d'objectif quadruplet, intégrant quatre éléments alignés avec précision pour offrir une correction des couleurs supérieure et un champ plat. Cette conception apochromatique élimine efficacement l'aberration chromatique et la courbure du champ, garantissant des images nettes et contrastées sur l'ensemble du champ de vision, ce qui est crucial pour l'astrophotographie. \n\u003c\/p\u003e\n\n\n\u003c\/div\u003e\n\n\u003cdiv class=\"image-side-2\" data-mce-style=\"text-align: start;\" style=\"text-align: start;\"\u003e\n\n\u003cimg alt=\"Askar 71F Quadruplet champ plat APO f\/6.9\" src=\"https:\/\/davidastro.com\/cdn\/shop\/files\/Askar-71F-1_1028x1028.png?v=1712853195\" style=\"margin-bottom: 16px; float: none;\"\u003e\n\n\u003c\/div\u003e\n\n\n\u003c\/div\u003e\n\n\n\u003cdiv data-mce-style=\"backgroundcolor: #0a0001; border-radius: 5px;\" style=\"background-color: #0a0001; border-radius: 5px;\"\u003e\n\n\u003ch3 style=\"color: white!important;\"\u003e\n\n Performances d'imagerie \n\n\u003c\/h3\u003e\n\n\u003chr\u003e\n\n\u003cdiv class=\"two-columns-section\"\u003e\n\n\n\u003cdiv class=\"text-side-2\"\u003e\n\n\u003cp style=\"color: white!important;\"\u003e \nAvec son ouverture de 71 mm et sa focale de 490 mm (f\/6,9), le 71F excelle en astrophotographie grand champ. Il est particulièrement adapté à la capture de grandes nébuleuses, de vastes champs d'étoiles et de vastes groupes de galaxies. Le rapport focal rapide f\/6,9 permet des temps d'exposition plus courts, ce qui facilite la collecte de données même dans des conditions de ciel loin d'être idéales.\n\u003c\/p\u003e\n\n\n\u003c\/div\u003e\n\n\n\u003c\/div\u003e\n\n\n\u003c\/div\u003e\n\n\n\u003c\/div\u003e\n\n\n\u003ch3\u003e Conception à champ plat\u003c\/h3\u003e\n\n\u003chr\u003e\n\n\u003cp\u003e\n La conception à champ plat du 71F garantit que les étoiles restent nettes et précises du centre aux bords du cadre. Ceci est particulièrement avantageux pour les astrophotographes utilisant de grands capteurs, car cela élimine le besoin d'un aplatisseur de champ séparé.\n\u003c\/p\u003e\n\n\n\u003ch3\u003e\n\n Qualité de fabrication\n\n\u003c\/h3\u003e\n\n\u003chr\u003e\n\n\u003cp\u003e\n Construit avec des matériaux de haute qualité, notamment un tube en aluminium usiné avec précision et un pare-buée. La construction robuste assure la stabilité et minimise la flexion, essentielle pour l'astrophotographie à longue exposition. Le pare-buée rétractable ajoute à sa portabilité.\n\u003c\/p\u003e\n\n\n\u003ch3\u003e\n\n Focuseur\n\n\u003c\/h3\u003e\n\n\u003chr\u003e\n\n\u003cp\u003e \nÉquipé d'un porte-oculaire à double vitesse de haute précision, permettant les réglages fins nécessaires pour obtenir une mise au point parfaite en astrophotographie. Le porte-oculaire est conçu pour gérer de lourdes charges utiles d’imagerie sans glisser, garantissant ainsi des performances constantes tout au long des longues sessions d’imagerie.\n\u003c\/p\u003e\n\n\n\u003ch3\u003e\n\n Portabilité\n\n\u003c\/h3\u003e\n\n\u003chr\u003e\n\n\u003cp\u003e\n Avec sa taille compacte et sa conception légère, le 71F est très portable, ce qui en fait un excellent choix pour les astrophotographes qui se rendent fréquemment sur des sites du ciel sombre. Sa portabilité ne compromet pas ses performances optiques, offrant un équilibre parfait pour les configurations d'imagerie mobiles.\n\u003c\/p\u003e\n\n\n\u003ch3\u003e\n\n Polyvalence\n\n\u003c\/h3\u003e\n\n\u003chr\u003e\n\n\u003cp\u003e\n Bien qu'essentiellement conçu pour l'astrophotographie, l'Askar 71F peut également être utilisé pour des observations visuelles avec les accessoires appropriés. Il offre des vues époustouflantes à grand champ des champs d'étoiles, des nébuleuses et des objets plus grands du ciel profond, ce qui en fait un instrument polyvalent pour diverses activités astronomiques.\n\u003c\/p\u003e\n\n\n\n\u003c\/li\u003e\n\n\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":48093955359005,"sku":"ASK-ASAPO71F","price":923.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-71F-1.png?v=1712853195"},{"product_id":"askar-0-75x-71f-reducer","title":"Askar 0.75x 71F Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e0.75x Reduction Factor\u003c\/li\u003e\n\u003cli\u003eTransforms Askar 71F to f\/5.2\u003c\/li\u003e\n\u003cli\u003eNew Focal Length: 369mm\u003c\/li\u003e\n\u003cli\u003eStandard 55mm Back Focus\u003c\/li\u003e\n\u003cli\u003eTriplet Optical Design\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 0.75x 71F Reducer\u003c\/h2\u003e\n\u003cp\u003eThe Askar 0.75x 71F Reducer transforms the Askar 71F refractor into a faster f\/5.2 imaging system with a new focal length of 369mm. This triplet reducer provides a standard 55mm back focus for easy camera integration and weighs just 0.23kg.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA Faster Askar 71F: The 0.75x Reduction to f\/5.2\u003c\/h3\u003e\n\u003cp\u003eBy reducing the native focal ratio of the Askar 71F to f\/5.2, this corrector significantly shortens required exposure times, allowing you to gather more signal on faint targets in a single session. The resulting 369mm focal length creates a wider field of view, ideal for framing large emission nebulae like the North American Nebula (NGC 7000) or sprawling star clusters. Its triplet optical design is engineered specifically to maintain image sharpness across the field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFull-Frame Correction with 55mm Standard Back Focus\u003c\/h3\u003e\n\u003cp\u003eThis reducer is also a dedicated field flattener, designed to produce sharp stars out to the corners of full-frame sensors. Imaging integration is straightforward thanks to a standard 55mm back focus, measured from the base of its M48 male thread, simplifying connection to your DSLR or dedicated astronomy camera. The design also incorporates threads for standard 2-inch filters, allowing you to use light pollution or narrowband filters without adding extra spacing to your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main benefit of using the Askar 0.75x Reducer with my 71F telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary benefit is speed. It reduces the focal ratio to f\/5.2, which cuts your exposure times significantly compared to the native f\/7 ratio. This allows you to collect more data on faint objects in less time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect my camera to the Askar 71F 0.75x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer provides a standard \u003cstrong\u003e55mm back focus\u003c\/strong\u003e from the base of its M48 male thread. You will need to use a combination of M48 spacers and adapters to place your camera's sensor at exactly this distance to achieve a flat field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs this Askar 0.75x reducer suitable for imaging the Andromeda Galaxy (M31) with a full-frame camera on the 71F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reduced focal length of \u003cstrong\u003e369mm\u003c\/strong\u003e provides a wide field of view that is excellent for large targets like the Andromeda Galaxy (M31) or the Heart and Soul Nebulae. The reducer is designed to flatten the field for full-frame sensors, ensuring sharp stars across the entire frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Askar 0.75x 71F Reducer also work as a field flattener?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it is a reducer-flattener. Its \u003cstrong\u003etriplet optical design\u003c\/strong\u003e corrects for field curvature, ensuring that stars are sharp from the center to the edges of the image, which is critical for astrophotography.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2-inch filters with the Askar 0.75x Reducer on my 71F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer's connection system is designed to accommodate standard 2-inch (M48x0.75) filters. You can thread them directly into the imaging train, making it easy to use narrowband or light pollution filters for targets like the Orion Nebula (M42).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the image circle of the Askar 0.75x 71F Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer is designed as a full-frame corrector. It effectively illuminates and flattens the field for camera sensors up to a 35mm format (43mm diagonal), making it compatible with a wide range of DSLRs and dedicated astronomy cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.75x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Length (with 71F)\u003c\/td\u003e\n\u003ctd\u003e369mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Ratio (with 71F)\u003c\/td\u003e\n\u003ctd\u003ef\/5.2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eTriplet\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\u003eRear Thread\u003c\/td\u003e\n\u003ctd\u003eM59*1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.23kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 0.75x 71F Reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.sharpstar-optics.com\/download_list_1\/7.html\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software \u0026amp; Drivers\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":49200895263005,"sku":"ASK-ASKAR71R","price":291.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-Reducer-71F-1.jpg?v=1727375509"},{"product_id":"askar-60f","title":"Askar 60F Flat-Field Astrograph","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e60mm Aperture Quadruplet APO Optics\u003c\/li\u003e\n\u003cli\u003e408mm Focal Length\u003c\/li\u003e\n\u003cli\u003ef\/6.8 Native Focal Ratio\u003c\/li\u003e\n\u003cli\u003e44mm Full-Frame Image Circle\u003c\/li\u003e\n\u003cli\u003eIntegrated Field Flattener\u003c\/li\u003e\n\u003cli\u003e2.86kg Gross Weight\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 60F Flat-Field Astrograph\u003c\/h2\u003e\n\u003cp\u003eThe Askar 60F Flat-Field astrograph delivers full-frame imaging capability in a compact package, integrating a 60mm quadruplet APO objective with a 408mm focal length. Its native f\/6.8 optical design features a built-in flattener that produces a corrected 44mm image circle, eliminating the need for separate corrective optics and complex back-focus calculations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eQuadruplet APO Optics: A Flat 44mm Image Circle at f\/6.8\u003c\/h3\u003e\n\u003cp\u003eThe core of the Askar 60F is its quadruplet air-spaced APO objective, which includes one ED glass element to ensure high-contrast images with minimal chromatic aberration. Unlike standard doublets or triplets that require a separate flattener, the 60F's integrated rear element corrects field curvature natively across a full 44mm image circle. This design simplifies your imaging train, allowing you to attach a full-frame camera, focus, and begin capturing sharp, pinpoint stars from edge to edge.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003ePortable Astrograph Design: 2.86kg Grab-and-Go System\u003c\/h3\u003e\n\u003cp\u003eEngineered for portability, the Askar 60F weighs just 2.86kg fully equipped with its included tube rings, handle, and 230mm Vixen dovetail plate. With a contracted length of only 289mm, it fits easily into carry-on luggage and pairs perfectly with lightweight tracking mounts. This makes it an ideal instrument for traveling to dark-sky sites or for quick setup in your backyard.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eReady-to-Image: Integrated Adapters and 50mm Focuser\u003c\/h3\u003e\n\u003cp\u003eThe Askar 60F arrives ready for astrophotography with a complete set of photographic adapters. The robust focuser provides 50mm of precise travel and terminates in a standard M64x0.75 thread. Included adapters step this down to M54 and M48, allowing direct connection to most dedicated astronomy cameras and DSLRs. The M48 adapter also features an internal thread for mounting standard 2\" filters, keeping your imaging train as short and rigid as possible.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAskar 60F vs. William Optics RedCat 61: Focal Length and Simplicity\u003c\/h3\u003e\n\u003cp\u003eWhen choosing a compact astrograph, a common comparison is the William Optics RedCat 61. The RedCat's f\/4.9 Petzval design is significantly faster, allowing for shorter sub-exposure times. However, the Askar 60F offers a distinct advantage with its longer 408mm focal length compared to the RedCat's 300mm, providing more image scale to better resolve details in smaller deep-sky objects or galaxy groups. For imagers seeking a straightforward, flat-field system with greater reach, the Askar 60F is the more targeted choice.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need a separate field flattener for the Askar 60F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, the Askar 60F has a \u003cstrong\u003ebuilt-in field flattener\u003c\/strong\u003e as part of its quadruplet optical design. It is engineered to deliver a flat field across a 44mm image circle, covering full-frame sensors without any additional corrective optics.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Askar 60F frame the North American Nebula (NGC 7000) with a full-frame camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 408mm focal length paired with a full-frame sensor provides a field of view that is ideal for capturing the entire North American Nebula (NGC 7000) and the adjacent Pelican Nebula (IC 5070) in a single, well-composed frame. The 44mm corrected image circle ensures stars will remain sharp across the entire image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Askar 60F suitable for a portable mount like the Sky-Watcher Star Adventurer GTi?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, absolutely. With a fully-equipped weight of just \u003cstrong\u003e2.86kg\u003c\/strong\u003e, the Askar 60F is an excellent match for compact GoTo equatorial mounts. This combination creates a powerful and highly portable grab-and-go imaging system capable of capturing high-quality deep-sky images.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat adapters are needed to connect a ZWO camera to the Askar 60F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar 60F includes a set of adapters, one of which is an \u003cstrong\u003eM48×0.75 adapter\u003c\/strong\u003e. This is the standard thread for most dedicated astronomy cameras, including those from ZWO. You can typically connect your camera directly to this adapter without needing to purchase anything additional.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Askar 60F for visual astronomy?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. While it is optically optimized for astrophotography, you can use the Askar 60F for visual observation by attaching a standard 1.25\" or 2\" diagonal and eyepiece. Its 408mm focal length makes it a superb instrument for wide-field sweeping of the Milky Way and observing large open star clusters.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the benefit of the Askar 60F's f\/6.8 focal ratio?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe f\/6.8 focal ratio offers an excellent balance between light-gathering speed and optical precision. It is fast enough for deep-sky imaging without being overly demanding on mount tracking accuracy. This moderate ratio also helps ensure excellent color correction and sharp star performance across the entire 44mm image circle.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eAperture\u003c\/td\u003e\n\u003ctd\u003e60mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e408mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/6.8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eObjective Lens\u003c\/td\u003e\n\u003ctd\u003eQuadruplet air-spaced APO (with one ED glass)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocuser Travel\u003c\/td\u003e\n\u003ctd\u003e50mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Length (Contracted)\u003c\/td\u003e\n\u003ctd\u003e289mm (with 1.25\" adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Length (Stretched)\u003c\/td\u003e\n\u003ctd\u003e369mm (with photo adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet Weight (OTA only)\u003c\/td\u003e\n\u003ctd\u003e2.36kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGross Weight (with rings \u0026amp; plate)\u003c\/td\u003e\n\u003ctd\u003e2.86kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear-End Adapters\u003c\/td\u003e\n\u003ctd\u003eM64×0.75 to M54, M54 to M54, M54 to M48 (with 2\" filter thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_60F_Flat-Field_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 60F OTA\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eTube Rings\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1 Pair\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eCarry Handle\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e230mm Vixen Dovetail Plate\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003ePhotographic Adapter Set\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_60F_Flat-Field_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":52851329466653,"sku":"ASK-ASAPO60F","price":699.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-60F-Flat-Field-1_1ba61c52-0d61-4c47-a32a-9a79b28bf7c4.jpg?v=1788401669"},{"product_id":"askar-91f","title":"Askar 91F Flat-Field Astrograph","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e91mm Aperture Quadruplet APO Optics\u003c\/li\u003e\n\u003cli\u003e609mm Focal Length at f\/6.7\u003c\/li\u003e\n\u003cli\u003e44mm Full-Frame Corrected Image Circle\u003c\/li\u003e\n\u003cli\u003eIntegrated Field Flattener Design\u003c\/li\u003e\n\u003cli\u003e3.92kg Net Weight\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 91F Flat-Field Astrograph\u003c\/h2\u003e\n\u003cp\u003eThe Askar 91F astrograph integrates a 91mm aperture with a 609mm focal length for a native f\/6.7 optical system. Its quadruplet APO objective, which includes one ED glass element, delivers a flat, color-corrected 44mm image circle that illuminates full-frame sensors without an external flattener. The entire optical tube weighs only 3.92kg, creating a portable yet powerful imaging instrument.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 91mm f\/6.7 Quadruplet APO with a 44mm Image Circle\u003c\/h3\u003e\n\u003cp\u003eThe core of the Askar 91F is its self-flattened optical design. Unlike traditional refractors that require a separate, carefully spaced field flattener, this quadruplet system has the correction built in. This eliminates the need to calculate back focus or purchase additional accessories, allowing you to connect your camera and start imaging immediately after achieving focus.\u003c\/p\u003e\n\u003cp\u003eThe 44mm image circle is specifically designed to cover full-frame CMOS and DSLR sensors, ensuring sharp, pinpoint stars from the center to the corners of your frame. The inclusion of one ED (Extra-low Dispersion) glass element in the air-spaced objective effectively suppresses chromatic aberration, resulting in high-contrast images with true-to-life color rendition, free of distracting purple fringing around bright stars.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e3-inch Rack-and-Pinion Focuser with 360° Rotation\u003c\/h3\u003e\n\u003cp\u003eTo support heavy full-frame cameras and filter wheels without flexure, the Askar 91F is equipped with a rigid 3-inch dual-speed rack-and-pinion focuser. The 1:10 fine adjustment knob allows for critical focus, while the 30mm of focuser travel accommodates a wide range of accessories. A 360° rotator at the rear of the focuser lets you frame your target perfectly without rotating the entire optical tube.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncluded Adapters:\u003c\/strong\u003e The package comes with a set of photographic adapters, including M54x0.75 and M48x0.75 connections, ensuring compatibility with most popular astronomy cameras and T-rings. The M48 adapter also includes a thread for 2-inch filters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisual Versatility:\u003c\/strong\u003e For visual use, the scope includes standard 2-inch and 1.25-inch adapters, making it a capable instrument for observing star clusters and nebulae, not just for imaging them.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 3.92kg Lightweight Design with Dual Finder Bases\u003c\/h3\u003e\n\u003cp\u003eEngineered for portability, the Askar 91F's main tube weighs just 3.92kg (4.52kg with rings and plate), making it an excellent match for mid-sized equatorial mounts. The retractable dew shield reduces the telescope's length to as little as 513mm for transport and storage. Thoughtful mechanical details enhance usability in the field.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDual Finder Mounts:\u003c\/strong\u003e Two finder bases are mounted on either side of the focuser, providing flexible mounting options for a guide scope and a finder scope simultaneously.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting Hardware:\u003c\/strong\u003e The included 230mm Vixen-style dovetail plate provides a secure connection to your mount and features 1\/4\" and 3\/8\" screw holes for direct attachment to a photo tripod for terrestrial viewing.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAskar 91F vs. Triplet APOs: The Advantage of an Integrated Flattener\u003c\/h3\u003e\n\u003cp\u003eWhen comparing the Askar 91F to a traditional triplet apochromat like the William Optics FLT 91, the primary distinction is the optical design philosophy. While both deliver excellent color correction, the triplet design requires an additional, separately purchased field flattener to achieve a flat field for astrophotography.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSimplicity and Cost:\u003c\/strong\u003e The Askar 91F's integrated flattener means there's no complex back-focus spacing to calculate and no extra accessory to buy. This simplifies the imaging train and reduces overall cost.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGuaranteed Correction:\u003c\/strong\u003e Because the flattener is part of the objective design, the optical correction is perfectly matched to the telescope, eliminating potential issues with third-party flatteners.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTrade-offs:\u003c\/strong\u003e A triplet with a separate flattener\/reducer can offer multiple focal ratios. The Askar 91F is optimized for its native 609mm focal length, prioritizing out-of-the-box imaging readiness over focal length flexibility.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main benefit of the Askar 91F's quadruplet design?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary benefit is its \u003cstrong\u003eself-flattened optical system\u003c\/strong\u003e. Unlike standard refractors that require a separate accessory, the Askar 91F has the field flattener built into its quadruplet objective. This ensures a perfectly flat 44mm image circle for full-frame cameras without the need to calculate back focus or buy extra components.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need to calculate back focus for the Askar 91F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The integrated flattener design means you do not need to calculate back focus. Simply attach your camera using the provided adapters, bring the telescope into focus using the focuser, and you are ready to image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Askar 91F perform on full-frame cameras like a Sony A7 series?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar 91F is designed specifically for full-frame cameras. Its \u003cstrong\u003e44mm corrected image circle\u003c\/strong\u003e fully illuminates the sensor of a Sony A7, Canon R, or Nikon Z series camera, providing pinpoint stars across the entire frame without vignetting or distorted stars in the corners.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of mount is needed for the 4.52kg Askar 91F OTA?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWith a fully loaded weight of 4.52kg (including rings and dovetail plate), the Askar 91F is well-suited for mid-sized equatorial mounts with a payload capacity of 25-30 lbs (11-14 kg) or more. Mounts like the Sky-Watcher HEQ5 or iOptron CEM26\/GEM28 can carry this telescope and associated imaging gear with excellent stability.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Askar 91F for visual observation of planets like Jupiter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. While optimized for astrophotography, its high-quality APO optics make it a very capable visual instrument. At 609mm, it provides medium power for observing Jupiter's moons and cloud bands or Saturn's rings. You would simply use the included 1.25\" or 2\" adapter with your choice of eyepieces.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat do the different adapter threads on the Askar 91F connect to?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar 91F includes a set of adapters to connect various devices. The primary connection types are:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eM64×1:\u003c\/strong\u003e The thread on the focuser drawtube itself.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM54×0.75:\u003c\/strong\u003e A common thread size for many larger-format astronomy cameras and filter wheels.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM48×0.75:\u003c\/strong\u003e The standard thread for 2\" filters and the most common connection for full-frame camera T-rings.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eAperture\u003c\/td\u003e\n\u003ctd\u003e91mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e609mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/6.7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eObjective Lens\u003c\/td\u003e\n\u003ctd\u003eQuadruplet air-spaced APO (including one ED glass)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocuser\u003c\/td\u003e\n\u003ctd\u003e3-inch dual-speed Rack \u0026amp; Pinion\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocuser Travel\u003c\/td\u003e\n\u003ctd\u003e30mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet Weight (OTA only)\u003c\/td\u003e\n\u003ctd\u003e3.92 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGross Weight (w\/ rings \u0026amp; plate)\u003c\/td\u003e\n\u003ctd\u003e4.52 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Length (Visual Config)\u003c\/td\u003e\n\u003ctd\u003e513mm (retracted) \/ 599mm (extended)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Length (Photo Config)\u003c\/td\u003e\n\u003ctd\u003e550mm (retracted) \/ 636mm (extended)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear-end Adapters\u003c\/td\u003e\n\u003ctd\u003eM64x1, M54x0.75, M48x0.75 (with 2\" filter thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_91F_Flat-Field_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 91F OTA\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eTube Rings\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1 Pair\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eCarry Handle\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e230mm Vixen Dovetail Plate\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003ePhotographic Adapter Set\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_91F_Flat-Field_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":52851329925405,"sku":"ASK-ASAPO91F","price":1399.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-91F-Flat-Field-1_23348316-55b6-4015-90af-dd56471b084f.jpg?v=1788401678"},{"product_id":"askar-111f","title":"Askar 111F 0.74× Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces Telescope Focal Ratio to f\/5.1\u003c\/li\u003e\n\u003cli\u003eCreates a 566mm Focal Length Imaging System\u003c\/li\u003e\n\u003cli\u003eTriplet Optical Design for Field Flattening\u003c\/li\u003e\n\u003cli\u003eProvides Standard 55mm Back Focus\u003c\/li\u003e\n\u003cli\u003eWeighs 0.5kg\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 111F 0.74× Reducer\u003c\/h2\u003e\n\u003cp\u003eThe Askar 111F 0.74× Reducer converts the telescope into a fast f\/5.1 astrograph, shortening the focal length to 566mm for wider fields of view. This triplet reducer establishes a standard 55mm back focus from its M48 male thread and weighs just 0.5kg, ensuring compatibility with a wide range of modern imaging cameras and accessories.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003ef\/5.1 Speed: A 0.74x Reduction for Wider Fields\u003c\/h3\u003e\n\u003cp\u003eBy reducing the focal ratio to f\/5.1, this accessory significantly cuts down the required exposure time for faint deep-sky objects. The corresponding 566mm focal length widens the field of view, allowing you to frame large targets like the Andromeda Galaxy (M31) or the North America Nebula (NGC 7000) in their entirety on a full-frame sensor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eOptical Correction: A 3-Element Design for Flat Fields\u003c\/h3\u003e\n\u003cp\u003eThe internal triplet lens design corrects for field curvature, ensuring stars remain sharp and round from the center to the edge of the frame. This level of correction is critical for modern, large-format CMOS and CCD sensors, eliminating optical distortions that would otherwise elongate stars in the corners of your images.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eMechanical Design: 55mm Back Focus and Integrated Filter Threads\u003c\/h3\u003e\n\u003cp\u003eEngineered for seamless integration, the reducer presents a standard 55mm back focus distance measured from the base of its M48 male camera connection. This simplifies the process of adding off-axis guiders or filter wheels into your imaging train. The reducer attaches to the telescope's focuser via an M68x1 thread, and the camera-side adapter includes threads for standard 2-inch (M48x0.75) filters.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main benefit of the Askar 111F 0.74x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary benefit is speed. By converting the Askar 111F to an \u003cstrong\u003ef\/5.1\u003c\/strong\u003e system with a \u003cstrong\u003e566mm\u003c\/strong\u003e focal length, it reduces exposure times by approximately 45% compared to the native focal ratio. This allows you to capture more data on faint objects in less time while also providing a wider field of view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I achieve the correct 55mm spacing for the 111F 0.74x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003e55mm back focus\u003c\/strong\u003e is measured from the base of the M48 male thread on the reducer to your camera's sensor. Most dedicated astronomy cameras and DSLR\/mirrorless camera T-rings are designed to this 55mm standard, so in many cases, you can connect your camera directly. If you add a filter wheel or off-axis guider, you must use extension rings to ensure the total distance remains exactly 55mm.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use filters with the Askar 111F 0.74x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer features a built-in M48x0.75 thread on the camera side, which allows you to directly attach standard \u003cstrong\u003e2-inch astronomical filters\u003c\/strong\u003e. This is ideal for using light pollution, narrowband, or LRGB filters without needing a separate filter drawer or wheel for simple setups.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the 111F 0.74x Reducer change my image of the Andromeda Galaxy (M31) with the Askar 111F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe native focal length of the Askar 111F is too long to fit the entire Andromeda Galaxy (M31) and its satellite galaxies on a full-frame sensor. By shortening the focal length to \u003cstrong\u003e566mm\u003c\/strong\u003e, the 0.74x Reducer provides a field of view wide enough to capture the full expanse of the galaxy in a single frame, making it an essential accessory for imaging large celestial targets.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the 111F 0.74x Reducer work with my full-frame camera on the Askar 111F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the \u003cstrong\u003etriplet\u003c\/strong\u003e optical design is corrected for a large image circle sufficient for full-frame sensors. It effectively flattens the field to ensure that stars in the corners of a full-frame image remain sharp and are not affected by coma or field curvature.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Askar 111F 0.74x Reducer compatible with other telescopes?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this reducer is an optically matched accessory designed specifically for the Askar 111F APO Triplet Refractor. Using it with other telescopes will likely result in poor optical correction and an inability to reach focus.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Length\u003c\/td\u003e\n\u003ctd\u003e566mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/5.1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eTriplet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (from base of M48 male thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Connection Thread\u003c\/td\u003e\n\u003ctd\u003eM68x1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.5 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_111F_Flat-Field_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":52851331006749,"sku":"ASK-ASAPO111R","price":419.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-111F-0-74-Reducer-1_ab87a539-90f5-488c-aeaf-5554073315a8.jpg?v=1788401687"},{"product_id":"askar-131f","title":"Askar 131F Flat-Field APO Refractor","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e131mm Aperture\u003c\/li\u003e\n\u003cli\u003ef\/7.5 Focal Ratio\u003c\/li\u003e\n\u003cli\u003eQuadruplet Air-Spaced APO Optical Design\u003c\/li\u003e\n\u003cli\u003eIncludes one ED Glass Element\u003c\/li\u003e\n\u003cli\u003e44mm Full-Frame Image Circle\u003c\/li\u003e\n\u003cli\u003eIntegrated Field Flattener\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 131F Flat-Field APO Refractor\u003c\/h2\u003e\n\u003cp\u003eThe Askar 131F Flat-Field refractor combines a 131mm aperture with a 983mm focal length in a native f\/7.5 optical system designed for serious astrophotography. Its quadruplet air-spaced APO objective, which includes one ED glass element, delivers a flat, color-corrected 44mm image circle without the need for an external flattener. With a gross weight of 9.4kg including rings and dovetail plate, this telescope integrates optical correction directly into the design, simplifying your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e131mm f\/7.5 Quadruplet APO: Color-Free, Flat-Field Imaging\u003c\/h3\u003e\n\u003cp\u003eThe core of the 131F is its advanced quadruplet objective lens. This design uses four air-spaced elements, including one ED (Extra-low Dispersion) glass element, to aggressively suppress chromatic aberration. Unlike standard doublets or triplets, this configuration corrects for color fringing and field curvature across the 44mm image circle, producing pinpoint stars on a dark background without requiring additional corrective optics.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e44mm Image Circle: Full-Frame Ready, No Flattener Required\u003c\/h3\u003e\n\u003cp\u003eThe defining feature of the Askar 131F is its \"self-flattening\" optical system. This eliminates the most common point of failure and complexity in imaging setups: calculating and achieving the correct back focus for a separate flattener. The 44mm image circle fully illuminates full-frame sensors, and with the included M48 and M54 adapters, you can directly attach your camera, focus, and begin imaging immediately.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eNo Additional Purchases:\u003c\/strong\u003e The integrated flattener means you save the cost and weight of a separate optical corrector.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eZero Back Focus Calculation:\u003c\/strong\u003e Simply attach your camera via the appropriate adapter and use the 30mm of focuser travel to achieve a sharp, flat field.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFilter Integration:\u003c\/strong\u003e The M54 to M48 adapter includes standard M48x0.75 filter threads, allowing you to easily add 2-inch filters to your imaging train.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e9.4kg Gross Weight: Robust Mechanics and 30mm Focuser Travel\u003c\/h3\u003e\n\u003cp\u003eEngineered for stability, the Askar 131F weighs 9.4kg when fully assembled with its included tube rings, handle, and 300mm Losmandy-style dovetail plate. The OTA itself has a net weight of 7.9kg and a variable length from 878mm to 1026mm depending on the adapter used and dew shield position. High-quality CNC machining ensures precise alignment, while the robust focuser provides 30mm of travel for fine-tuning focus with a variety of cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAskar 131F vs. Triplet APOs: The Integrated Flattener Advantage\u003c\/h3\u003e\n\u003cp\u003eWhile many high-end refractors use a triplet objective, they almost always require an additional field flattener or reducer\/flattener for astrophotography. This introduces complexity, potential tilt, and critical back focus spacing requirements that must be met with precision spacers.\u003c\/p\u003e\n\u003cp\u003eThe Askar 131F's quadruplet design incorporates that correction into the main optical tube. This provides a significant advantage: you get a guaranteed flat field optimized for the telescope's native 983mm focal length without any extra components or calculations. While a triplet with a separate flattener might offer more flexibility with reducers, the 131F delivers perfect out-of-the-box performance for full-frame imaging at its designed focal ratio.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main advantage of the Askar 131F's self-flattening design?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary advantage is simplicity and reliability. You do not need to purchase a separate field flattener or calculate the precise 55mm (or other) back focus distance. The Askar 131F's quadruplet optics deliver a flat 44mm image circle right out of the box, eliminating a major source of frustration in astrophotography.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat size camera sensors will the Askar 131F's 44mm image circle cover?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 44mm image circle is large enough to fully illuminate \u003cstrong\u003efull-frame sensors\u003c\/strong\u003e (typically 43.3mm diagonal) found in cameras like the ZWO ASI6200 or Sony A7 series. It will also easily cover smaller APS-C and Micro Four Thirds sensors with no vignetting.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Askar 131F perform on large deep-sky objects like the Andromeda Galaxy (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 983mm focal length provides excellent image scale for resolving detail in medium-to-large targets. When paired with a full-frame camera, the Askar 131F can frame the entirety of the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000), capturing these expansive objects with sharp stars from edge to edge.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of mount is required for the Askar 131F's 9.4kg weight?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFor imaging, a mount with a payload capacity of at least 40-50 lbs (18-22 kg) is recommended. The total weight of the Askar 131F is 9.4kg (about 20.7 lbs), and you must also account for your camera, guide scope, and other accessories. A mount like the Sky-Watcher EQ6-R Pro or Celestron CGX would be a suitable choice.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2-inch filters with the Askar 131F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The included photographic adapter set contains an M54-to-M48 adapter that is threaded to accept standard \u003cstrong\u003eM48x0.75 (2-inch) filters\u003c\/strong\u003e. This allows you to easily incorporate narrowband or light pollution filters into your imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Askar 131F need a separate dew heater?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eLike all refractors, the objective lens is exposed to the night air and can collect dew. While the extendable dew shield (which increases the total length to 963mm or 1026mm) helps, using a dedicated dew heater strip around the objective is highly recommended for all-night imaging sessions, especially in humid conditions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eAperture\u003c\/td\u003e\n\u003ctd\u003e131mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e983mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/7.5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eObjective Lens\u003c\/td\u003e\n\u003ctd\u003eQuadruplet air-spaced APO (including one ED glass)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocuser Travel\u003c\/td\u003e\n\u003ctd\u003e30mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet Weight (OTA only)\u003c\/td\u003e\n\u003ctd\u003e7.9kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGross Weight (with rings \u0026amp; plate)\u003c\/td\u003e\n\u003ctd\u003e9.4kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Length (Contracted)\u003c\/td\u003e\n\u003ctd\u003e878mm (with 1.25\" adapter) \/ 941mm (with photo adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Length (Stretched)\u003c\/td\u003e\n\u003ctd\u003e963mm (with 1.25\" adapter) \/ 1026mm (with photo adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear-End Adapters\u003c\/td\u003e\n\u003ctd\u003eM78×1 to M54×0.75, M54×0.75 to M54×0.75, M54×0.75 to M48×0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thread\u003c\/td\u003e\n\u003ctd\u003eM48×0.75 (on M54-M48 adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_131F_Flat-Field_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e131F OTA\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eTube Rings\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1 Pair\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eHandle\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e300mm Losmandy Dovetail Plate\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003ePhotographic Adapter Set\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_131F_Flat-Field_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":52851331236125,"sku":"ASK-ASAPO131F","price":2799.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-131F-Flat-Field-1_466f55e4-2cbf-413b-ab14-1372829037b5.jpg?v=1788401697"},{"product_id":"askar-0-75x-reducer-for-60f","title":"Askar 60F 0.75x Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e0.75x Focal Reduction\u003c\/li\u003e\n\u003cli\u003eReduces Focal Length to 311mm\u003c\/li\u003e\n\u003cli\u003eCreates a Fast f\/5.1 Focal Ratio\u003c\/li\u003e\n\u003cli\u003e44mm Full-Frame Image Circle\u003c\/li\u003e\n\u003cli\u003eStandard 55mm Back Focus\u003c\/li\u003e\n\u003cli\u003eTriplet Optical Design\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 60F 0.75x Reducer\u003c\/h2\u003e\n\u003cp\u003eDesigned exclusively for the Askar 60F refractor, this 0.75x Reducer transforms the telescope into a faster, wider imaging system, shortening the focal length to 311mm and the focal ratio to a swift f\/5.1. The three-element triplet optical design simultaneously flattens the field, delivering a corrected 44mm image circle that fully illuminates full-frame sensors with a standard 55mm back focus.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e0.75x Reduction: Transform Your 60F to a Fast f\/5.1 Astrograph\u003c\/h3\u003e\n\u003cp\u003eBy converting your Askar 60F to an f\/5.1 instrument, this reducer significantly cuts down required exposure times, allowing you to gather more signal in less time. This speed is critical for capturing faint details in nebulae or for imaging transient objects. The wider field of view produced by the 311mm focal length makes it possible to frame large targets like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000) in their entirety.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eTriplet Optics: A Flat 44mm Image Circle for Full-Frame Sensors\u003c\/h3\u003e\n\u003cp\u003eThe reducer employs a three-element, air-spaced triplet lens configuration that acts as a field flattener, correcting for the optical aberrations inherent in a curved focal plane. This results in a 44mm image circle, large enough to cover modern full-frame CMOS and CCD sensors without vignetting. You will see sharp, point-like stars across the entire frame, from the center to the very corners of your images.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eSeamless Integration: 55mm Back Focus and Built-in Filter Cell\u003c\/h3\u003e\n\u003cp\u003eEngineered for convenience, the reducer features a standard 55mm back focus from its M48 male threads, simplifying the process of connecting DSLRs, mirrorless cameras, or dedicated astronomy cameras with standard spacers. A key feature is the integrated M48x0.75 thread at the front of the adapter, which allows you to directly attach 2-inch filters. This eliminates the need for a separate filter drawer or wheel in your imaging train, saving precious back focus and reducing complexity.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main benefit of using the 60F 0.75x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary benefits are speed and field of view. The reducer converts the Askar 60F to a faster \u003cstrong\u003ef\/5.1\u003c\/strong\u003e optical system, which dramatically shortens exposure times. It also widens the field of view by reducing the focal length to \u003cstrong\u003e311mm\u003c\/strong\u003e, allowing you to capture larger celestial objects in a single frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this 0.75x reducer work with telescopes other than the Askar 60F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. This reducer is optically designed and threaded specifically for the Askar 60F refractor. Using it with other telescopes will result in poor optical performance and an inability to reach focus.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the 60F 0.75x Reducer support full-frame cameras?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. It is designed to produce a flat, fully-illuminated \u003cstrong\u003e44mm image circle\u003c\/strong\u003e, which is large enough to cover the sensors of full-frame DSLR, mirrorless, and dedicated astronomy cameras without significant vignetting.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I install a 2-inch filter with this 60F reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer's adapter has a built-in \u003cstrong\u003eM48x0.75 thread\u003c\/strong\u003e at the front. You can simply screw any standard 2-inch astronomy filter directly into this thread, placing it securely in the optical path without needing a separate filter holder.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 60F 0.75x Reducer help when imaging a large target like the Andromeda Galaxy (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eBy reducing the focal length to \u003cstrong\u003e311mm\u003c\/strong\u003e, the reducer provides a much wider field of view than the native telescope. This allows you to frame the entirety of the Andromeda Galaxy (M31) and its satellite galaxies M32 and M110 in a single shot. The faster \u003cstrong\u003ef\/5.1\u003c\/strong\u003e focal ratio also helps capture the faint outer arms of the galaxy more efficiently.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 55mm back focus of the Askar 60F Reducer difficult to achieve?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, \u003cstrong\u003e55mm\u003c\/strong\u003e is the industry standard for back focus. Most DSLR and mirrorless cameras with a standard 10mm T-ring achieve this distance perfectly. For dedicated astronomy cameras, achieving 55mm is straightforward using a combination of standard M48 extension tubes that are readily available.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.75x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Length\u003c\/td\u003e\n\u003ctd\u003e311mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/5.1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eTriplet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (from M48 male thread base)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear-end Thread\u003c\/td\u003e\n\u003ctd\u003eM50x1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.2kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 60F 0.75x Reducer\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eFront Metal Dust Cap\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eRear Metal Dust Cap\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":52851335430429,"sku":"ASK-ASKAR60R","price":279.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-60F-0-75x-Reducer-1_c52c17eb-7904-4f98-9eee-8d2f4173fd83.jpg?v=1788401754"},{"product_id":"askar-0-75x-reducer-for-91f","title":"Askar 91F 0.75x Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces focal ratio to a fast f\/5\u003c\/li\u003e\n\u003cli\u003e0.75x reduction factor for wider fields of view\u003c\/li\u003e\n\u003cli\u003eTriplet optical design provides field-flattening correction\u003c\/li\u003e\n\u003cli\u003eStandard 55mm back focus from the M48 thread\u003c\/li\u003e\n\u003cli\u003eLightweight 0.3kg construction\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 91F 0.75x Reducer\u003c\/h2\u003e\n\u003cp\u003eThe Askar 91F 0.75x Reducer transforms its dedicated telescope into a faster, wider imaging system, shortening the native focal length to 455mm and the focal ratio to a rapid f\/5. This triplet reducer is engineered to provide full-frame, field-flattened correction while maintaining a standard 55mm back focus for seamless integration with your existing M48-threaded imaging train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eFaster f\/5 Imaging: The 0.75x Optical Advantage\u003c\/h3\u003e\n\u003cp\u003eBy decreasing the focal ratio to f\/5, this 0.75x reducer significantly cuts down required exposure times, allowing you to gather more signal on faint targets in less time. The wider field of view is ideal for capturing large-scale celestial objects that would otherwise be too expansive for the telescope's native field, such as the Andromeda Galaxy (M31) or the entire Veil Nebula complex.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eTriplet Design with 55mm Back Focus for Full-Frame Sensors\u003c\/h3\u003e\n\u003cp\u003eThe air-spaced triplet optical design not only reduces the focal length but also acts as a dedicated field flattener, ensuring sharp, point-like stars across a full-frame sensor. It establishes a standard 55mm back focus distance from its M48 male thread, simplifying the connection to DSLRs, mirrorless cameras, and dedicated astronomy cameras with common spacers.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntegrated Filter Thread:\u003c\/strong\u003e A built-in M48x0.75 thread allows you to mount 2-inch filters directly into the reducer, placing them securely within the optical path without needing a separate filter drawer.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSecure Connection:\u003c\/strong\u003e The reducer attaches to the Askar 91F focuser via a robust M59*1 thread, ensuring a rigid, tilt-free connection for imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCNC Machining:\u003c\/strong\u003e The entire housing is CNC-machined for precision and durability, and includes threaded metal dust caps for protection when not in use.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eImaging with the Askar 91F: Native vs. f\/5 Reduced\u003c\/h3\u003e\n\u003cp\u003eThis reducer offers a critical choice for astrophotographers. Using the Askar 91F at its native focal length provides higher magnification, perfect for framing smaller galaxies or planetary nebulae where image scale is paramount. Attaching the 0.75x reducer is the superior option for large emission nebulae and star clusters, where its light-gathering speed and wider perspective are essential for capturing the entire object in a single frame.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the 91F 0.75x Reducer do for my Askar 91F telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 91F 0.75x Reducer shortens your telescope's focal ratio to a faster f\/5 and focal length to 455mm. This provides two main benefits: a \u003cstrong\u003ewider field of view\u003c\/strong\u003e to fit larger objects in the frame, and \u003cstrong\u003eshorter exposure times\u003c\/strong\u003e to capture faint details more efficiently.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I connect the Askar 91F 0.75x Reducer to my camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer provides a standard \u003cstrong\u003e55mm back focus\u003c\/strong\u003e from the base of its M48 male thread. This is a common standard for most astronomy cameras and DSLRs with the appropriate T-ring. You simply add or remove M48 spacers until the distance from the reducer's flange to your camera sensor is exactly 55mm.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2-inch filters with the 91F 0.75x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The reducer has a built-in M48x0.75 female thread on the camera side, allowing you to directly screw in standard 2-inch astronomy filters. This is convenient for using light pollution or narrowband filters without needing a separate filter wheel or drawer.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Askar 91F 0.75x Reducer also a field flattener?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it is. The triplet optical design is engineered to provide field-flattening correction specifically for the Askar 91F telescope. This ensures that stars remain sharp and round across the entire image, even at the edges of a full-frame sensor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich targets benefit most from the 91F 0.75x Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis reducer is ideal for large deep-sky objects that require a wide field of view. Excellent targets include the \u003cstrong\u003eNorth American Nebula (NGC 7000)\u003c\/strong\u003e, the \u003cstrong\u003eAndromeda Galaxy (M31)\u003c\/strong\u003e, and large star-forming regions like the Heart and Soul Nebulae (IC 1805 and IC 1848).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhen should I *not* use the 91F 0.75x Reducer with my Askar 91F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou should image without the reducer when your target is small and requires maximum image scale. For example, most galaxies like the Whirlpool Galaxy (M51), smaller planetary nebulae like the Ring Nebula (M57), or any planetary imaging would be better suited to the telescope's native, longer focal length.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.75x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResulting Focal Length\u003c\/td\u003e\n\u003ctd\u003e455mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResulting Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eTriplet, Air-Spaced\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus\u003c\/td\u003e\n\u003ctd\u003e55mm (from M48 thread base)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Side Thread\u003c\/td\u003e\n\u003ctd\u003eM59*1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Side Thread\u003c\/td\u003e\n\u003ctd\u003eM48x0.75 (Male)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thread\u003c\/td\u003e\n\u003ctd\u003eM48x0.75 (Female, for 2\" filters)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.3kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":52851336904989,"sku":"ASK-ASKAR91R","price":279.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-91F-0-75x-Reducer-1_234100f2-15d6-4254-a83f-7aaf11c45959.jpg?v=1788401763"},{"product_id":"askar-111f-flat-field-astrograph","title":"Askar 111F Flat-Field Astrograph","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e111mm Aperture Quadruplet APO Optics\u003c\/li\u003e\n\u003cli\u003e766mm Focal Length at f\/6.9\u003c\/li\u003e\n\u003cli\u003e44mm Full-Frame Corrected Image Circle\u003c\/li\u003e\n\u003cli\u003eIntegrated Field Flattener Design\u003c\/li\u003e\n\u003cli\u003e5.74kg Net Weight\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 111F Flat-Field Astrograph\u003c\/h2\u003e\n\u003cp\u003eThe Askar 111F astrograph integrates a 111mm aperture with a 766mm focal length for a native f\/6.9 optical system. Its quadruplet APO objective, which includes one ED glass element, delivers a flat, color-corrected 44mm image circle that illuminates full-frame sensors without an external flattener. The optical tube weighs 5.74kg, pairing serious light-gathering with true out-of-the-box imaging readiness.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA 111mm f\/6.9 Quadruplet APO with a 44mm Image Circle\u003c\/h3\u003e\n\u003cp\u003eThe core of the Askar 111F is its self-flattened optical design. Unlike traditional refractors that require a separate, carefully spaced field flattener, this quadruplet system — three elements in the front group and one in the rear — has the correction built in. This eliminates the need to calculate back focus or purchase additional accessories, allowing you to connect your camera and start imaging immediately after achieving focus.\u003c\/p\u003e\n\u003cp\u003eThe 44mm image circle is specifically designed to cover full-frame CMOS and DSLR sensors, ensuring sharp, pinpoint stars from the center to the corners of your frame. The inclusion of one ED (Extra-low Dispersion) glass element in the air-spaced objective effectively suppresses chromatic aberration, while a built-in baffle inside the main tube blocks stray light for higher contrast and true-to-life color rendition, free of distracting purple fringing around bright stars.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e3-inch Rack-and-Pinion Focuser with 360° Rotation\u003c\/h3\u003e\n\u003cp\u003eTo support heavy full-frame cameras and filter wheels without flexure, the Askar 111F is equipped with a rigid 3-inch dual-speed rack-and-pinion focuser. The 1:10 fine adjustment knob — protected by its own cap to prevent damage — allows for critical focus, while the 30mm of focuser travel accommodates a wide range of accessories. A 360° graduated rotator at the rear of the focuser lets you frame your target to a precise angle without rotating the entire optical tube.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncluded Adapters:\u003c\/strong\u003e The package comes with a four-piece photographic adapter set, including M54x0.75 and M48x0.75 connections, ensuring compatibility with most popular astronomy cameras and T-rings. The M48 adapter also includes a thread for 2-inch filters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisual Versatility:\u003c\/strong\u003e For visual use, the scope includes standard 2-inch and 1.25-inch adapters, making it a capable instrument for observing star clusters and nebulae, not just for imaging them.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA Retractable Dew Shield and Triple Finder Bases\u003c\/h3\u003e\n\u003cp\u003eThe Askar 111F's main tube weighs 5.74kg (6.76kg with rings and plate), making it a natural match for mid to large equatorial mounts. The retractable dew shield reduces the telescope's length to as little as 664mm for transport and storage, and the CNC-machined tube carries the F-series' classic blue and white finish. Thoughtful mechanical details enhance usability in the field.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThree Finder Mounts:\u003c\/strong\u003e Finder bases sit on either side of the focuser, and a third slot is built into the carry handle, letting you reposition a finder or guide scope without disassembly and mount multiple accessories at once.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting Hardware:\u003c\/strong\u003e The included 300mm Vixen-style dovetail plate provides a secure connection to your mount and features 1\/4\" and 3\/8\" screw holes for direct attachment to a photo tripod for terrestrial viewing.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAskar 111F vs. Triplet APOs: The Advantage of an Integrated Flattener\u003c\/h3\u003e\n\u003cp\u003eWhen comparing the Askar 111F to a traditional triplet apochromat like the William Optics FLT 110, the primary distinction is the optical design philosophy. While both deliver excellent color correction, the triplet design requires an additional, separately purchased field flattener to achieve a flat field for astrophotography.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSimplicity and Cost:\u003c\/strong\u003e The Askar 111F's integrated flattener means there's no complex back-focus spacing to calculate and no extra accessory to buy. This simplifies the imaging train and reduces overall cost.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGuaranteed Correction:\u003c\/strong\u003e Because the flattener is part of the objective design, the optical correction is perfectly matched to the telescope, eliminating potential issues with third-party flatteners.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTrade-offs:\u003c\/strong\u003e A triplet with a separate flattener\/reducer can offer multiple focal ratios. The Askar 111F is optimized for its native 766mm focal length, prioritizing out-of-the-box imaging readiness — though a dedicated 111F 0.74× reducer is available separately for a wider, faster field.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main benefit of the Askar 111F's quadruplet design?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary benefit is its \u003cstrong\u003eself-flattened optical system\u003c\/strong\u003e. Unlike standard refractors that require a separate accessory, the Askar 111F has the field flattener built into its quadruplet objective. This ensures a perfectly flat 44mm image circle for full-frame cameras without the need to calculate back focus or buy extra components.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need to calculate back focus for the Askar 111F?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The integrated flattener design means you do not need to calculate back focus. Simply attach your camera using the provided adapters, bring the telescope into focus using the focuser, and you are ready to image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Askar 111F perform on full-frame cameras like a Sony A7 series?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar 111F is designed specifically for full-frame cameras. Its \u003cstrong\u003e44mm corrected image circle\u003c\/strong\u003e fully illuminates the sensor of a Sony A7, Canon R, or Nikon Z series camera, providing pinpoint stars across the entire frame without vignetting or distorted stars in the corners.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of mount is needed for the 6.76kg Askar 111F OTA?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWith a fully loaded weight of 6.76kg (including rings and dovetail plate), and more once a camera, filter wheel and guide scope are added, the Askar 111F is best paired with mounts rated for roughly 30-40 lbs (14-18 kg) of imaging payload. Mounts such as the Sky-Watcher EQ6-R Pro or iOptron GEM45\/CEM40 will carry this telescope and its accessories with the stability that a 766mm focal length demands.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Askar 111F for visual observation of planets like Jupiter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. While optimized for astrophotography, its high-quality APO optics make it a very capable visual instrument. At 766mm with 111mm of aperture, it provides ample power and light-gathering for observing Jupiter's moons and cloud bands or Saturn's rings. You would simply use the included 1.25\" or 2\" adapter with your choice of eyepieces.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat do the different adapter threads on the Askar 111F connect to?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Askar 111F includes a set of adapters to connect various devices. The primary connection types are:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eM78×1:\u003c\/strong\u003e The thread on the focuser drawtube itself.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM54×0.75:\u003c\/strong\u003e A common thread size for many larger-format astronomy cameras and filter wheels.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM48×0.75:\u003c\/strong\u003e The standard thread for 2\" filters and the most common connection for full-frame camera T-rings.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eAperture\u003c\/td\u003e\n\u003ctd\u003e111mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e766mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/6.9\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eObjective Lens\u003c\/td\u003e\n\u003ctd\u003eQuadruplet air-spaced APO (including one ED glass)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle\u003c\/td\u003e\n\u003ctd\u003e44mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocuser\u003c\/td\u003e\n\u003ctd\u003e3-inch dual-speed Rack \u0026amp; Pinion\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocuser Travel\u003c\/td\u003e\n\u003ctd\u003e30mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack Focus (Imaging Mode)\u003c\/td\u003e\n\u003ctd\u003e43-73mm from M48x0.75 \/ 61-91mm from M54x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet Weight (OTA only)\u003c\/td\u003e\n\u003ctd\u003e5.74 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGross Weight (w\/ rings \u0026amp; plate)\u003c\/td\u003e\n\u003ctd\u003e6.76 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Length (Visual Config)\u003c\/td\u003e\n\u003ctd\u003e664mm (retracted) \/ 751mm (extended)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Length (Photo Config)\u003c\/td\u003e\n\u003ctd\u003e728mm (retracted) \/ 815mm (extended)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear-end Adapters\u003c\/td\u003e\n\u003ctd\u003eM78x1-M54x0.75, M54x0.75-M54x0.75, M54x0.75-M48x0.75 (with 2\" filter thread)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_111F_Flat-Field_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAskar 111F OTA\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eTube Rings\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1 Pair\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eCarry Handle\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e300mm Vixen Dovetail Plate\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003ePhotographic Adapter Set\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar_111F_Flat-Field_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":52851337232669,"sku":"ASK-ASKAR111F","price":2099.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-111f-Flat-Field-Astrograph_446ebebc-539c-4180-bcf7-9ac30c529e50.jpg?v=1788898954"},{"product_id":"askar-0-74x-reducer-for-131f","title":"Askar 131F 0.74× Reducer","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces telescope focal ratio to f\/5.6\u003c\/li\u003e\n\u003cli\u003eAchieves a 733.6mm final focal length\u003c\/li\u003e\n\u003cli\u003eTriplet optical design for field flattening\u003c\/li\u003e\n\u003cli\u003eStandard 55mm back focus from the M48 thread\u003c\/li\u003e\n\u003cli\u003eWeighs 0.56kg\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAskar 131F 0.74× Reducer\u003c\/h2\u003e\n\u003cp\u003eThe Askar 131F 0.74x Reducer converts the Askar 131F refractor into a faster f\/5.6 astrograph with a final focal length of 733.6mm. This dedicated triplet reducer provides a wider field of view and significantly shortens exposure times, all while maintaining a precise 55mm back focus distance and weighing just 0.56kg.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003e0.74x Reduction: Transforming the 131F to an f\/5.6 Astrograph\u003c\/h3\u003e\n\u003cp\u003eBy reducing the native f\/7.5 optics of the Askar 131F to a faster f\/5.6, this reducer cuts required exposure times by nearly half. This speed is critical for capturing faint details in nebulae and galaxies. The triplet optical design doesn't just reduce the focal length to 733.6mm; it also flattens the field, ensuring stars remain sharp and round across a full-frame sensor from the center to the corners of your image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eMechanical Design: 55mm Back Focus and Full-Frame Correction\u003c\/h3\u003e\n\u003cp\u003eEngineered for seamless integration, the reducer maintains the industry-standard 55mm back focus distance, measured from the base of its M48 male thread. This simplifies the process of connecting your DSLR, mirrorless, or dedicated astronomy camera with standard adapters and off-axis guiders. The main body features a rear-end M72x1 thread for a secure connection to the telescope's focuser, and the CNC-machined housing ensures precise optical alignment.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does the Askar 131F 0.74× Reducer do to my telescope's focal length?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 0.74x Reducer shortens the Askar 131F's native focal length to \u003cstrong\u003e733.6mm\u003c\/strong\u003e and speeds up the focal ratio from f\/7.5 to \u003cstrong\u003ef\/5.6\u003c\/strong\u003e. This provides a wider field of view and gathers light more quickly, reducing your total imaging time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the back focus of the Askar 131F 0.74× Reducer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe required back focus is \u003cstrong\u003e55mm\u003c\/strong\u003e, measured from the base of the male M48 thread on the reducer. This is a standard distance that works directly with most DSLR cameras using a T-ring and many dedicated astronomy camera setups.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Askar 131F 0.74× Reducer help me image the Andromeda Galaxy (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Andromeda Galaxy is a very large target. The reducer's \u003cstrong\u003e733.6mm\u003c\/strong\u003e focal length provides a wider field of view, allowing you to capture the entire galaxy and its faint outer arms within a single frame using a full-frame or APS-C sensor. The faster \u003cstrong\u003ef\/5.6\u003c\/strong\u003e optics will also help you capture more signal in less time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Askar 131F 0.74× Reducer suitable for imaging large nebulae like the North American Nebula (NGC 7000)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. The wide field of view provided by the \u003cstrong\u003e733.6mm\u003c\/strong\u003e focal length is ideal for framing large emission nebulae like NGC 7000. Furthermore, the fast \u003cstrong\u003ef\/5.6\u003c\/strong\u003e focal ratio is highly effective at capturing faint hydrogen-alpha signal, making it a perfect match for such targets.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of optical correction does the Askar 131F 0.74× Reducer provide?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer uses a \u003cstrong\u003etriplet lens design\u003c\/strong\u003e. This multi-element configuration is engineered not only to reduce the focal length but also to act as a field flattener, correcting for the natural field curvature of the main optics. This ensures that stars are sharp across the entire imaging sensor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow much does the Askar 131F 0.74× Reducer weigh?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe reducer weighs \u003cstrong\u003e0.56kg\u003c\/strong\u003e. This is an important consideration for ensuring your mount remains properly balanced after adding the reducer and camera to the optical train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduction Factor\u003c\/td\u003e\n\u003ctd\u003e0.74x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Length\u003c\/td\u003e\n\u003ctd\u003e733.6mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReduced Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/5.6\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLens Design\u003c\/td\u003e\n\u003ctd\u003eTriplet\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\u003e0.56kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRear-end Thread\u003c\/td\u003e\n\u003ctd\u003eM72x1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/askar-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eAskar 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":52851337429277,"sku":"ASK-ASKAR131FRD","price":419.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Askar-131F-0-74-Reducer-1_efb7cdda-5cf2-46a8-a24c-8bb2c26ac7dd.jpg?v=1788401779"}],"url":"https:\/\/davidastro.com\/fr-us\/collections\/askar-f-flat-field-astrographs.oembed","provider":"David Astro","version":"1.0","type":"link"}