{"product_id":"svbony-sv545-petzval-astrograph","title":"SVBONY SV545 45mm f\/4.5 Petzval APO Astrograph Lens","description":"\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-10_20251219101629_5486.webp?v=1791669959\" alt=\"SVBONY SV545 45mm f\/4.5 Petzval astrograph lens\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe SVBONY SV545 is a 45 mm, 203 mm focal length Petzval apochromatic astrograph working at f\/4.5. It uses a five-element, three-group objective with fully multi-coated (FMC) optics and a built-in flat field, so stars stay round toward the edge of the frame without a separate flattener. A one-piece helical focuser, a lockable 360° rotator and an M48x0.75 male thread at the back make it a compact, self-contained wide-field imaging lens.\u003c\/p\u003e\n\u003cp\u003eSVBONY ships it with an EAF mount kit, a carry handle with an integrated Vixen-style finder saddle, a dovetail plate, a camera angle adjuster, a 2″ filter holder already assembled to the lens, front and rear covers and a soft padded case.\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-12_20251219101635_4375.webp?v=1791669959\" alt=\"SVBONY SV545 Petzval astrograph feature overview\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThis is a good match if you:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eImage large deep-sky fields:\u003c\/strong\u003e 203 mm of focal length frames big emission nebulae, dark-nebula regions and star fields such as Cygnus, Orion and the Milky Way core.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWant a fast, portable rig:\u003c\/strong\u003e f\/4.5 keeps sub-exposures short, and the short tube rides on compact star trackers and small equatorial mounts.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrefer a simple imaging train:\u003c\/strong\u003e the flat field is built in, so the camera threads straight to the M48 back without a corrector.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlan to automate focus:\u003c\/strong\u003e the helical focuser is prepared for an electronic auto focuser, and the EAF mount kit is included.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eIt works well as a first dedicated astrograph and as a wide-field companion to a longer imaging telescope.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePetzval APO objective:\u003c\/strong\u003e five elements in three groups, fully multi-coated.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e45 mm aperture, 203 mm focal length, f\/4.5:\u003c\/strong\u003e a short, fast focal length for wide-field framing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuilt-in flat field:\u003c\/strong\u003e no external flattener is needed for edge-to-edge star shapes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHelical focuser:\u003c\/strong\u003e one-piece integrated focusing, prepared for an EAF with the included mount kit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLockable 360° rotator:\u003c\/strong\u003e frame the target without loosening the camera.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM48x0.75 male back thread:\u003c\/strong\u003e standard connection for astronomy cameras, filter wheels and DSLR T-rings.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2″ filter holder:\u003c\/strong\u003e supplied already assembled to the lens.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAll-metal body:\u003c\/strong\u003e SVBONY describes sealed construction with protective coatings for humid or dusty conditions.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-16_20251219101713_3423.webp?v=1791669959\" alt=\"SVBONY SV545 built-in flat field\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-18_20251219101718_2772.webp?v=1791669960\" alt=\"SVBONY SV545 helical focuser and EAF readiness\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-20_20251219101723_5148.webp?v=1791669959\" alt=\"SVBONY SV545 lockable 360 degree rotator\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eA Petzval astrograph splits its optics into a front objective group and a rear corrector group spaced inside the tube. Because the field-flattening group is part of the design, the focal plane arrives flat at the camera without an add-on corrector, and there is no backfocus spacer stack to tune for the flattener. SVBONY's 3-group, 5-element layout keeps the element count moderate for optical consistency and a compact body, while the fully multi-coated surfaces control reflections around bright stars.\u003c\/p\u003e\n\u003cp\u003eAt f\/4.5 and 203 mm the SV545 gathers signal quickly and covers a wide patch of sky, which suits broadband colour imaging under dark skies as well as narrowband or dual-band work from the suburbs.\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-14_20251219101641_3151.webp?v=1791669959\" alt=\"SVBONY SV545 3-group 5-element Petzval optical design\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWide-field nebula imaging:\u003c\/strong\u003e North America and Pelican, Cygnus Loop, Rosette, Orion's Sword and Heart and Soul regions fit comfortably.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMilky Way star fields:\u003c\/strong\u003e rich star clouds and dark-nebula regions at a short focal length.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNarrowband and dual-band imaging:\u003c\/strong\u003e through the included 2″ filter holder.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTravel imaging:\u003c\/strong\u003e a compact lens that packs into its padded case with the accessories.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-22_20251219101729_5597.webp?v=1791669960\" alt=\"SVBONY SV545 camera and filter compatibility\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCamera connection:\u003c\/strong\u003e M48x0.75 male thread at the back. SVBONY states the standard threads and back focus suit DSLRs, astronomy cameras and filter wheels without extra adapters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFilters:\u003c\/strong\u003e 2″ filters mount in the supplied filter holder.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocusing:\u003c\/strong\u003e manual helical focus, with an EAF mount kit included for an electronic focuser.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting:\u003c\/strong\u003e dovetail plate supplied; the handle carries a Vixen-style finder saddle for a guide scope or finder.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFraming:\u003c\/strong\u003e lockable 360° rotator plus a camera angle adjuster in the box.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eIf you want to check a particular camera, filter wheel or guider against the SV545's back end, send us your setup and we will work through the spacing with you.\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-23_20251219101734_2821.webp?v=1791669959\" alt=\"SVBONY SV545 imaging train connection\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-24_20251219101755_4933.webp?v=1791669959\" alt=\"SVBONY SV545 handle and finder saddle\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-26_20251219101800_4141.webp?v=1791669959\" alt=\"SVBONY SV545 all-metal construction\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-28_20251219101805_2095.webp?v=1791669960\" alt=\"SVBONY SV545 specifications and dimensions\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eWhat's in the Box\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e1 x SV545 astro APO camera lens\u003c\/li\u003e\n\u003cli\u003e1 x EAF mount kit\u003c\/li\u003e\n\u003cli\u003e1 x handle with integrated Vixen-style finder saddle\u003c\/li\u003e\n\u003cli\u003e1 x dovetail plate\u003c\/li\u003e\n\u003cli\u003e1 x camera angle adjuster\u003c\/li\u003e\n\u003cli\u003e1 x 2″ filter holder (assembled to the lens)\u003c\/li\u003e\n\u003cli\u003e1 x plastic lens cover\u003c\/li\u003e\n\u003cli\u003e1 x M48 metal lens cover\u003c\/li\u003e\n\u003cli\u003e1 x soft padded case\u003c\/li\u003e\n\u003cli\u003eWrench and screws\u003c\/li\u003e\n\u003cli\u003e1 x instruction manual\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/W9317B-Description-30_20251219101810_8152.webp?v=1791669960\" alt=\"SVBONY SV545 package contents\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eImaging lens:\u003c\/strong\u003e the SV545 is built as an astrograph for cameras. It has no diagonal or eyepiece in the box.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight figure:\u003c\/strong\u003e SVBONY publishes an estimated weight of 2750 g and does not state whether it is the bare lens or the packed kit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount and camera sold separately:\u003c\/strong\u003e the lens needs a tracking mount and a camera; the SVBONY add-ons on this page cover filters and imaging accessories.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStyle option:\u003c\/strong\u003e SVBONY also offers an SV545 Photography Set; this listing is the SV545 OTA style.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. The flat field is built in, so the camera threads onto the M48 back, the rotator sets framing, and the helical focuser brings stars to focus. There is no external flattener spacing to work out.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it need a field flattener?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. SVBONY designs the SV545 with a built-in flat field for edge-to-edge stars.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I add an electronic focuser?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes. The focuser is prepared for an EAF, and the EAF mount kit is in the box.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat filters does it take?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e2″ filters, in the 2″ filter holder supplied assembled to the lens.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill it work with a DSLR?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes, through an M48 T-ring for your camera body. Astronomy cameras connect to the same M48x0.75 thread.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is it best used for?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eWide-field deep-sky imaging of large nebulae and Milky Way regions at 203 mm and f\/4.5.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 45 mm, 203 mm f\/4.5 Petzval astrograph with a built-in flat field, helical EAF-ready focuser, lockable rotator, 2″ filter holder and M48 back, supplied with handle, dovetail and padded case. Add a camera and a tracking mount and it is ready for wide-field imaging.\u003c\/p\u003e","brand":"SvBony","offers":[{"title":"SV545 OTA","offer_id":67722231316591,"sku":"W9317B","price":569.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/SV545-1_20260211084332_9921.webp?v=1791670140","url":"https:\/\/ontariotelescope.com\/products\/svbony-sv545-petzval-astrograph","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}