{"title":"Classic Cat","description":"","products":[{"product_id":"william-optics-minicat-51-wifd","title":"William Optics MiniCat 51 WIFD","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics MiniCat 51 WIFD\u003c\/strong\u003e is a compact 51mm f\/3.5 Petzval astrograph designed for very wide-field deep-sky astrophotography and fast portable imaging. With a 178mm focal length, 6-element Petzval optical design, and 43.2mm image circle, it is built for photographers and astrophotographers who want an ultra-fast travel-friendly imaging telescope.\u003c\/p\u003e\n\n\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\n\u003cp\u003eThe MiniCat 51 WIFD is best for astrophotographers who want a small, fast astrograph for wide nebulae, comets, Milky Way regions, star fields, and portable deep-sky imaging. It is especially useful for travel setups, lightweight mounts, APS-C cameras, and users who want a simplified flat-field imaging system.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFast f\/3.5 optics:\u003c\/strong\u003e Captures faint targets efficiently in shorter exposures.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e178mm focal length:\u003c\/strong\u003e Excellent for ultra-wide-field astrophotography.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e6-element Petzval design:\u003c\/strong\u003e Provides a corrected imaging field with no separate flattener required.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWIFD internal focuser:\u003c\/strong\u003e Helps maintain stable focusing and camera alignment.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompact travel size:\u003c\/strong\u003e Ideal for lightweight imaging rigs and portable mounts.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eWide-field deep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eLarge nebula imaging\u003c\/li\u003e\n\u003cli\u003eComet imaging\u003c\/li\u003e\n\u003cli\u003eMilky Way region imaging\u003c\/li\u003e\n\u003cli\u003eTravel astrophotography\u003c\/li\u003e\n\u003cli\u003eAPS-C and Micro Four Thirds camera systems\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe MiniCat 51 WIFD includes a tilt adjuster rotator and M54 to M48 adapter. It supports common camera mount ecosystems including Canon EF, Canon RF, Nikon F, Nikon Z, Sony E, Pentax K, Micro Four Thirds, and Fuji X. It is compatible with electronic automatic focusing systems and uses a Vixen to Arca-Swiss style dovetail arrangement.\u003c\/p\u003e\n\n\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThe MiniCat 51 WIFD is designed primarily for astrophotography. William Optics notes that because of the very fast f\/3.5 optical design, edge stars may not be as round as with other RedCat models; aberration correction software can help improve peripheral star shapes, especially on APS-C sensors.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003ch3\u003eIs the MiniCat 51 WIFD good for beginners?\u003c\/h3\u003e\u003cp\u003eIt can be a good choice for beginners who are specifically building a compact astrophotography rig, but it is best used with an equatorial mount, camera, and basic imaging workflow.\u003c\/p\u003e\u003ch3\u003eWhat type of astrophotography is it best for?\u003c\/h3\u003e\u003cp\u003eIt is best for ultra-wide-field deep-sky imaging, large nebulae, comets, Milky Way regions, and travel astrophotography.\u003c\/p\u003e\u003ch3\u003eDoes it need a field flattener?\u003c\/h3\u003e\u003cp\u003eNo. Its Petzval optical design is built to provide a flat field without a separate flattener.\u003c\/p\u003e\u003ch3\u003eWhat camera formats work with it?\u003c\/h3\u003e\u003cp\u003eAPS-C is recommended, while full-frame is listed as compatible and may require more attention to edge correction.\u003c\/p\u003e\n\n\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eThe William Optics MiniCat 51 WIFD is a strong choice for astrophotographers who want the fastest and most portable Cat-series astrograph for large targets and travel imaging. Choose it for wide-field imaging speed and compact size. Consider a slower Cat model if your priority is cleaner edge performance without software correction.\u003c\/p\u003e\n\n\u003ch2\u003eOptical Diagram Reports\u003c\/h2\u003e\u003cp\u003eThe following optical report graphics are included for customers who want to review optical performance, spot behavior, and field quality.\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-minicat-51-wifd-spot-diagram.jpg?v=1779643994\" alt=\"William Optics MiniCat 51 WIFD spot diagram optical report\"\u003e\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-minicat-51-wifd-eccentricity-fwhm.jpg?v=1779644001\" alt=\"William Optics MiniCat 51 WIFD eccentricity and FWHM optical report\"\u003e\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-minicat-51-wifd-optical-diagram-2.jpg?v=1779644011\" alt=\"William Optics MiniCat 51 WIFD optical diagram report\"\u003e\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53153989918831,"sku":"T-C-MINI-RD","price":1257.2,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-minicat-51-wifd-perspective-1.jpg?v=1779643883"},{"product_id":"william-optics-cat-51-wifd","title":"William Optics Cat 51 WIFD","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics Cat 51 WIFD\u003c\/strong\u003e is a compact 51mm f\/4.9 Petzval astrograph designed for wide-field astrophotography and portable imaging. With a 250mm focal length, 48mm image circle, and William Optics Internal Focuser Design, it is built for astrophotographers who want a small, high-quality imaging telescope with a flat field and simple camera connection.\u003c\/p\u003e\n\n\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eThe Cat 51 WIFD is best for beginner to intermediate astrophotographers who want a portable astrograph for large nebulae, star fields, comets, and travel-friendly deep-sky imaging. It is also a good fit for experienced imagers who want a compact wide-field telescope for a second imaging rig.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e51mm aperture:\u003c\/strong\u003e Compact and easy to mount for travel or grab-and-go imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e250mm focal length:\u003c\/strong\u003e Excellent for wide-field nebulae and star fields.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e4-element Petzval design:\u003c\/strong\u003e Flat-field imaging without a separate field flattener.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e48mm image circle:\u003c\/strong\u003e Supports full-frame, APS-C, and Micro Four Thirds cameras.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWIFD focuser:\u003c\/strong\u003e Helps maintain better stability with camera accessories.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eWide-field deep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eLarge nebula imaging\u003c\/li\u003e\n\u003cli\u003eStar-field imaging\u003c\/li\u003e\n\u003cli\u003eComet imaging\u003c\/li\u003e\n\u003cli\u003eTravel astrophotography\u003c\/li\u003e\n\u003cli\u003eLightweight equatorial mount setups\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe Cat 51 WIFD includes a tilt adjuster, rotator, and M54 to M48 adapter. It supports common camera mount ecosystems including Canon EF, Canon RF, Nikon F, Nikon Z, Sony E, Pentax K, Micro Four Thirds, and Fuji X. Customers should confirm camera adapter requirements, focusing setup, and mount capacity before purchase.\u003c\/p\u003e\n\n\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThe Cat 51 WIFD is primarily an astrophotography telescope. It is best recommended for imaging customers rather than customers looking for a dedicated visual observing telescope.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003ch3\u003eIs the Cat 51 WIFD good for beginners?\u003c\/h3\u003e\u003cp\u003eYes, it is one of the more approachable William Optics astrographs for customers starting a compact astrophotography system, provided they also have a suitable tracking mount and camera.\u003c\/p\u003e\u003ch3\u003eWhat type of astrophotography is it best for?\u003c\/h3\u003e\u003cp\u003eIt is best for wide-field deep-sky imaging, large nebulae, star fields, and travel astrophotography.\u003c\/p\u003e\u003ch3\u003eDoes it need a flattener?\u003c\/h3\u003e\u003cp\u003eNo. Its Petzval design provides a flat imaging field without a separate field flattener.\u003c\/p\u003e\u003ch3\u003eWhat camera formats work with it?\u003c\/h3\u003e\u003cp\u003eIt supports full-frame, APS-C, and Micro Four Thirds cameras.\u003c\/p\u003e\n\n\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eThe William Optics Cat 51 WIFD is a strong choice for astrophotographers who want a compact, high-quality, wide-field Petzval astrograph for portable deep-sky imaging. Choose it for easy transport, simple flat-field imaging, and large-target astrophotography.\u003c\/p\u003e\n\n\u003ch2\u003eOptical Diagram Reports\u003c\/h2\u003e\u003cp\u003eThe following optical report graphics are included for customers who want to review optical performance.\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-cat-51-wifd-spot-diagram.jpg?v=1779645003\" alt=\"William Optics Cat 51 WIFD spot diagram optical report\"\u003e\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-cat-51-wifd-longitudinal-aberration.jpg?v=1779645014\" alt=\"William Optics Cat 51 WIFD longitudinal aberration optical report\"\u003e\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/william-optics-cat-51-wifd-wavefront-report.jpg?v=1779645021\" alt=\"William Optics Cat 51 WIFD wavefront optical report\"\u003e\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154015805551,"sku":"L-RC51RDIII-AI-DRAFT","price":1117.2,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/Redcat-51-perspective-1__25884.jpg?v=1766571054"},{"product_id":"william-optics-cat-61-wifd","title":"William Optics Cat 61 WIFD","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics Cat 61 WIFD\u003c\/strong\u003e is a compact 61mm f\/4.9 Petzval astrograph designed for wide-field deep-sky astrophotography, portable imaging, and full-frame camera support. With a 300mm focal length, 46mm image circle, and William Optics Internal Focuser Design, it gives astrophotographers a small but capable imaging telescope with a flat field and stable focusing.\u003c\/p\u003e\n\n\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eThe Cat 61 WIFD is best for beginner to intermediate astrophotographers who want more aperture and reach than a 51mm astrograph while still keeping the system compact and travel-friendly. It is also useful for advanced imagers building a lightweight secondary wide-field rig.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e61mm aperture:\u003c\/strong\u003e More light gathering than smaller travel astrographs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e300mm focal length:\u003c\/strong\u003e Ideal for wide nebulae, star fields, and larger deep-sky targets.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e4-element Petzval design:\u003c\/strong\u003e Flat-field imaging without a separate field flattener.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e46mm image circle:\u003c\/strong\u003e Supports full-frame, APS-C, and Micro Four Thirds cameras.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWIFD focuser:\u003c\/strong\u003e Helps maintain focus stability with camera accessories.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eWide-field deep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eNebula and star-field imaging\u003c\/li\u003e\n\u003cli\u003ePortable astrophotography setups\u003c\/li\u003e\n\u003cli\u003eFull-frame, APS-C, and Micro Four Thirds imaging\u003c\/li\u003e\n\u003cli\u003eLightweight equatorial mount systems\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe Cat 61 WIFD includes a tilt adjuster, M60 to M54 rotator, and M54 to M48 adapter. It supports common camera mount ecosystems including Canon EF, Canon RF, Nikon F, Nikon Z, Sony E, Pentax K, Micro Four Thirds, and Fuji X. Customers should confirm camera adapter, focuser, guide scope, and mount capacity needs before purchase.\u003c\/p\u003e\n\n\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThe Cat 61 WIFD is primarily an astrophotography telescope. It is best recommended for customers building an imaging system rather than customers looking for a simple visual observing telescope.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003ch3\u003eIs the Cat 61 WIFD good for beginners?\u003c\/h3\u003e\u003cp\u003eYes, it can be a strong beginner astrophotography telescope when paired with a suitable tracking mount and camera.\u003c\/p\u003e\u003ch3\u003eWhat type of astrophotography is it best for?\u003c\/h3\u003e\u003cp\u003eIt is best for wide-field deep-sky imaging, including nebulae, star fields, large galaxies, and travel imaging setups.\u003c\/p\u003e\u003ch3\u003eDoes it need a field flattener?\u003c\/h3\u003e\u003cp\u003eNo. Its 4-element Petzval design provides a flat imaging field without a separate flattener.\u003c\/p\u003e\u003ch3\u003eWhat camera formats work with it?\u003c\/h3\u003e\u003cp\u003eIt supports full-frame, APS-C, and Micro Four Thirds cameras.\u003c\/p\u003e\n\n\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eThe William Optics Cat 61 WIFD is a strong choice for astrophotographers who want a compact, full-frame-capable Petzval astrograph with more reach than a 51mm model. Choose it for portable deep-sky imaging, large nebulae, and simple flat-field camera setups.\u003c\/p\u003e\n\n\u003ch2\u003eOptical Diagram Reports\u003c\/h2\u003e\u003cp\u003eThe following optical report graphics are included for customers who want to review optical performance.\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/upload-1779645442351.jpg?v=1779645444\" alt=\"William Optics Cat 61 WIFD optical diagram report\"\u003e\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/upload-1779645455058.jpg?v=1779645456\" alt=\"William Optics Cat 61 WIFD optical diagram report\"\u003e\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154047885423,"sku":"T-C-61RD","price":1539.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/upload-1779645409495.jpg?v=1779645411"},{"product_id":"william-optics-cat-71-wifd","title":"William Optics Cat 71 WIFD","description":"\u003cp\u003eThe \u003cstrong\u003eWilliam Optics Cat 71 WIFD\u003c\/strong\u003e is a 71mm f\/4.9 Petzval astrograph designed for wide-field deep-sky astrophotography with full-frame camera support. With a 350mm focal length, flat-field optical design, and William Optics Internal Focuser Design, it gives astrophotographers a compact but more capable imaging platform than smaller 51mm and 61mm models.\u003c\/p\u003e\n\n\u003ch2\u003eWho Is This Product Best For?\u003c\/h2\u003e\u003cp\u003eThe Cat 71 WIFD is best for intermediate astrophotographers who want a portable imaging telescope with more aperture and reach while still maintaining a wide field of view. It is well suited to full-frame, APS-C, and Micro Four Thirds camera users imaging nebulae, galaxies, star fields, and large deep-sky objects.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Choose This Product?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e71mm aperture:\u003c\/strong\u003e More light gathering than smaller Cat-series models while staying portable.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e350mm focal length:\u003c\/strong\u003e A versatile wide-field focal length for many deep-sky targets.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePetzval optical design:\u003c\/strong\u003e Flat-field imaging without requiring a separate field flattener.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWIFD focuser:\u003c\/strong\u003e Helps maintain focus stability and balance with camera accessories.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFull-frame support:\u003c\/strong\u003e A good fit for modern full-frame, APS-C, and Micro Four Thirds cameras.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eWide-field deep-sky astrophotography\u003c\/li\u003e\n\u003cli\u003eNebula and star-field imaging\u003c\/li\u003e\n\u003cli\u003ePortable and backyard imaging systems\u003c\/li\u003e\n\u003cli\u003eFull-frame and APS-C camera setups\u003c\/li\u003e\n\u003cli\u003eLightweight to mid-size equatorial mounts\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe Cat 71 WIFD is designed for astrophotography camera systems and includes camera-side adapter support for common imaging setups. Customers should confirm camera adapter needs, guide scope setup, focuser requirements, filter wheel clearance, and mount capacity before purchase.\u003c\/p\u003e\n\n\u003ch2\u003eImportant Limitations\u003c\/h2\u003e\u003cp\u003eThe Cat 71 WIFD is primarily an astrophotography telescope. It is best recommended for imaging customers rather than customers looking for a simple visual observing telescope.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003ch3\u003eIs the Cat 71 WIFD good for beginners?\u003c\/h3\u003e\u003cp\u003eIt can be used by a beginner building a serious astrophotography system, but it is best for users who understand tracking mounts, camera connection, focusing, guiding, and image processing.\u003c\/p\u003e\u003ch3\u003eWhat type of astrophotography is it best for?\u003c\/h3\u003e\u003cp\u003eIt is best for wide-field deep-sky imaging, including nebulae, star fields, large galaxies, and portable imaging setups.\u003c\/p\u003e\u003ch3\u003eDoes it need a field flattener?\u003c\/h3\u003e\u003cp\u003eNo. The Petzval optical design provides a flat imaging field without a separate field flattener.\u003c\/p\u003e\u003ch3\u003eWhat camera formats work with it?\u003c\/h3\u003e\u003cp\u003eThe Cat 71 WIFD is designed for modern astronomy cameras, including full-frame, APS-C, and Micro Four Thirds imaging setups.\u003c\/p\u003e\n\n\u003ch2\u003eOur Recommendation\u003c\/h2\u003e\u003cp\u003eThe William Optics Cat 71 WIFD is a strong choice for astrophotographers who want a portable Petzval astrograph with more reach and aperture than the smaller Cat-series models. Choose it for full-frame-capable wide-field imaging, nebulae, star fields, and a compact but serious deep-sky setup.\u003c\/p\u003e\n\n\u003ch2\u003eOptical Diagram Reports\u003c\/h2\u003e\u003cp\u003eThe following optical report graphics are included for customers who want to review optical performance.\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/upload-1779645502215.jpg?v=1779645504\" alt=\"William Optics Cat 71 WIFD optical diagram report\"\u003e\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/upload-1779645512594.jpg?v=1779645514\" alt=\"William Optics Cat 71 WIFD optical diagram report\"\u003e\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":53154053292143,"sku":"T-C-71RD","price":2518.6,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/upload-1779645472685.jpg?v=1779645474"}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/collections\/Redcat-51-perspective-1__25884.jpg?v=1779820127","url":"https:\/\/ontariotelescope.com\/collections\/classic-cat.oembed","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}