{"title":"Renvois coudés SVBONY","description":"\u003cp\u003eLes renvois coudés SVBONY dévient le faisceau à 90° ou à 45° pour une position d'observation confortable. Les renvois à miroir diélectrique, SV188P et SV223 ClickLock en 1.25\" et 2\", offrent une réflectivité élevée, tandis que le miroir zénithal SV188 et le miroir en laiton SV221 sont des options plus simples. Les prismes SV221 et SV222 donnent une image redressée à 45° ou à 90°, utile pour les longues-vues et l'observation terrestre.\u003c\/p\u003e\u003cp\u003eLa bague ClickLock maintient l'oculaire centré et bien serré.\u003c\/p\u003e","products":[{"product_id":"svbony-sv188-90-zenith-mirror-diagonal-125in","title":"SVBONY SV188 90° Zenith Mirror Diagonal - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eProvides a comfortable 90-degree viewing angle\u003c\/li\u003e\n\u003cli\u003eStandard 1.25\" barrel fits most refractor and SCT focusers\u003c\/li\u003e\n\u003cli\u003eFeatures a 90% reflectivity mirror for bright images\u003c\/li\u003e\n\u003cli\u003eDurable all-metal housing maintains optical alignment\u003c\/li\u003e\n\u003cli\u003eSingle-screw clamp secures 1.25\" eyepieces\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\u003eSVBONY SV188 Zenith Mirror Diagonal 1.25inch 90 Degree\u003c\/h2\u003e\n\u003cp\u003eThe SVBONY SV188 Zenith Mirror Diagonal redirects the light path of your refractor telescope by 90 degrees, placing the eyepiece in a much more comfortable position for astronomical viewing. Its standard 1.25-inch barrel ensures compatibility with a vast range of telescopes and eyepieces, while the internal mirror's 90% reflectivity preserves the brightness and clarity of the image delivered by your objective lens.\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\u003e90% Reflectivity Mirror for Brighter, Clearer Views\u003c\/h3\u003e\n\u003cp\u003eThe core of the SV188 is its mirror, which features a reflective coating that transmits 90% of the incoming light to your eyepiece. This level of reflectivity is crucial for preserving image brightness, especially when observing faint deep-sky objects like the Orion Nebula (M42) or distant galaxies. Unlike some entry-level prisms, a mirror diagonal introduces no chromatic aberration, ensuring that bright objects like Jupiter and Sirius remain free of false color.\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\u003eDurable Metal Housing \u0026amp; 1.25\" Refractor Compatibility\u003c\/h3\u003e\n\u003cp\u003eBuilt with a metal housing, the SVBONY SV188 is designed for durability and to hold the mirror in precise alignment, night after night. The 1.25-inch nosepiece and eyepiece holder are standard sizes, ensuring a secure fit in the focusers of most refractors, Schmidt-Cassegrains, and Maksutov-Cassegrains. A single locking screw provides a firm grip on your eyepieces.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eRefractor-Specific Design:\u003c\/strong\u003e This diagonal is optimized for telescopes where you view from the back of the tube.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNewtonian Limitation:\u003c\/strong\u003e The SV188 is not suitable for Newtonian reflectors. Its light path is too long, which prevents the telescope from reaching focus.\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\u003eSV188 Mirror vs. Prism Diagonal: A 90° Difference\u003c\/h3\u003e\n\u003cp\u003eWhile both mirror and prism diagonals provide a 90-degree viewing angle, they achieve it differently. The SV188's mirror reflects the light, which generally provides better color fidelity and light throughput compared to standard, uncoated prism diagonals. While high-end prisms can offer excellent views, a quality mirror diagonal like the SV188 is often a significant upgrade over the basic prism included with many beginner telescopes, yielding sharper and brighter images.\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\"\u003eWhy should I use the SVBONY SV188 diagonal with my refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary reason is comfort. Without a diagonal, viewing objects high in the sky through a refractor requires you to crouch or kneel in an awkward position. The SV188's \u003cstrong\u003e90-degree\u003c\/strong\u003e angle lets you observe comfortably while seated, leading to steadier views and longer, more enjoyable sessions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the SVBONY SV188 work with my Newtonian telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, the SV188 is \u003cstrong\u003enot suitable for Newtonian reflectors\u003c\/strong\u003e. Newtonian telescopes have a very specific focal plane and require a secondary mirror, not a diagonal, to direct light to the side-mounted focuser. Adding this diagonal would prevent the telescope from achieving focus.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the SV188 diagonal affect views of the Moon in my 80mm refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe SV188 will provide bright, sharp views of the Moon. Its \u003cstrong\u003e90% reflectivity\u003c\/strong\u003e ensures minimal light loss, keeping lunar features like crater walls and rilles high in contrast. Because it's a mirror diagonal, it won't introduce any chromatic aberration (color fringing), preserving the true color and fine detail along the terminator.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the SVBONY SV188 provide a \"correct\" image for terrestrial viewing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. Like all standard astronomical mirror diagonals, the SV188 provides an image that is correct up-and-down but is reversed left-to-right. This is perfectly acceptable for astronomy, but for terrestrial viewing (like bird watching), you would need a 45-degree correct-image erecting prism.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the SVBONY SV188 on a Maksutov-Cassegrain like a Celestron NexStar 4SE?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, absolutely. Maksutov-Cassegrain and Schmidt-Cassegrain telescopes function like refractors in that they have a rear-mounted focuser. The SV188 is perfectly compatible and is a common accessory for these types of telescopes to achieve a more comfortable viewing position.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the advantage of the SV188 mirror diagonal over a basic prism diagonal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe SV188's main advantages are typically better light transmission and color fidelity. Its \u003cstrong\u003e90% reflectivity\u003c\/strong\u003e mirror surface avoids the potential light absorption and scattering of a lower-quality prism and does not introduce the slight chromatic aberration that can occur as light passes through the glass of a prism.\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\u003eEyepiece Connection\u003c\/td\u003e\n\u003ctd\u003e1.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" (or 2\" with optional adapter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEyepiece Clamp\u003c\/td\u003e\n\u003ctd\u003eSingle screw\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReflectivity\u003c\/td\u003e\n\u003ctd\u003e90%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHousing Material\u003c\/td\u003e\n\u003ctd\u003eMetal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Telescope Types\u003c\/td\u003e\n\u003ctd\u003eRefractors, Schmidt-Cassegrains, Maksutov-Cassegrains\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIncompatible Telescope Types\u003c\/td\u003e\n\u003ctd\u003eNewtonian Reflectors\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\"\u003eSV188 1.25\" Zenith Mirror Diagonal\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\"\u003eDust Cap (Eyepiece Side)\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\"\u003eDust Cap (Telescope Side)\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\/svbony-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSVBONY 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SVBONY","offers":[{"title":"Default Title","offer_id":52861237461277,"sku":"SV-F9171A","price":34.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/SVBONY-SV188-Zenith-Mirror-Diagonal-1-25inch-90-Degree-For-Refractors-1_e283a9c2-ef17-4efb-bee3-fc97ff1c0caf.jpg?v=1788883436"},{"product_id":"svbony-sv188p-90-dielectric-mirror-diagonal-2in","title":"SVBONY SV188P 90° Dielectric Mirror Diagonal - 2\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n  \u003cli\u003e99% Reflectivity Dielectric Coatings\u003c\/li\u003e\n  \u003cli\u003e90-Degree Viewing Angle\u003c\/li\u003e\n  \u003cli\u003e11mm Thick Mirror Substrate\u003c\/li\u003e\n  \u003cli\u003eDurable Aluminum Alloy Body\u003c\/li\u003e\n  \u003cli\u003eBrass Compression Ring Eyepiece Holder\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\u003eSVBONY SV188P 99% Reflectivity 90-Degree Dielectric Mirror Diagonal\u003c\/h2\u003e\n          \u003cp\u003eThe SVBONY SV188P 90-Degree Dielectric Mirror Diagonal maximizes image brightness by delivering 99% reflectivity from its precision 11mm thick mirror. This design ensures that the absolute minimum amount of light is lost in the optical path, providing brighter, higher-contrast views through refractors and Cassegrain telescopes.\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\u003e99% Dielectric Mirror: Maximizing Light Throughput\u003c\/h3\u003e\n          \u003cp\u003eAt the core of the SV188P is a mirror with advanced dielectric coatings that achieve 99% reflectivity. Unlike standard aluminum or silver coatings that can degrade over time, these multi-layer coatings are highly durable and deliver consistent light transmission across the visible spectrum. The mirror itself is 11mm thick, providing excellent thermal stability to maintain a precise figure during temperature changes.\u003c\/p\u003e\n          \u003cul\u003e\n            \u003cli\u003e\n\u003cstrong\u003e99% Reflectivity:\u003c\/strong\u003e Transmits nearly all collected light to your eyepiece, resulting in visibly brighter images compared to diagonals with lower-grade coatings.\u003c\/li\u003e\n            \u003cli\u003e\n\u003cstrong\u003eDielectric Coatings:\u003c\/strong\u003e Offer superior durability and resistance to aging, ensuring the diagonal maintains its peak optical clarity for years of use.\u003c\/li\u003e\n            \u003cli\u003e\n\u003cstrong\u003e11mm Thick Mirror:\u003c\/strong\u003e Provides a stable optical surface that resists warping from temperature fluctuations, preserving image sharpness.\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\u003e90-Degree Ergonomics and Eyepiece Protection\u003c\/h3\u003e\n          \u003cp\u003eDesigned for comfortable observing, the 90-degree angle of the SV188P places the eyepiece in a natural position for viewing objects high in the sky, reducing neck strain during long sessions. The robust aluminum alloy body houses a non-marring brass compression ring, which secures your eyepieces firmly without scratching their barrels—a significant upgrade over simple set screw designs.\u003c\/p\u003e\n          \u003cul\u003e\n            \u003cli\u003e\n\u003cstrong\u003eComfortable Viewing Angle:\u003c\/strong\u003e The 90-degree bend is ideal for use with refractor and Cassegrain-style telescopes where the eyepiece would otherwise be at an awkward angle.\u003c\/li\u003e\n            \u003cli\u003e\n\u003cstrong\u003eBrass Compression Ring:\u003c\/strong\u003e Grips the eyepiece barrel uniformly, preventing scratches and ensuring a secure, centered fit.\u003c\/li\u003e\n            \u003cli\u003e\n\u003cstrong\u003eAluminum Alloy Construction:\u003c\/strong\u003e Provides a rigid, durable frame for the optical components, ensuring reliable alignment.\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\u003eSV188P's 99% Reflectivity vs. Standard Silver Diagonals\u003c\/h3\u003e\n          \u003cp\u003eWhile a standard silver-coated diagonal typically offers 95-97% reflectivity, the SVBONY SV188P's 99% dielectric coatings provide a measurable increase in image brightness. This difference is most apparent when observing faint deep-sky objects or resolving low-contrast details on planets at high magnification.\u003c\/p\u003e\n          \u003cul\u003e\n            \u003cli\u003e\n\u003cstrong\u003eBrighter Images:\u003c\/strong\u003e The 2-4% increase in light transmission can be the difference between spotting a faint galaxy arm or seeing only the core.\u003c\/li\u003e\n            \u003cli\u003e\n\u003cstrong\u003eEnhanced Durability:\u003c\/strong\u003e Dielectric coatings do not tarnish or oxidize like silver, offering a longer operational life with consistent optical clarity.\u003c\/li\u003e\n            \u003cli\u003e\n\u003cstrong\u003eTrade-off:\u003c\/strong\u003e The SV188P produces an image that is upright but mirror-reversed (left-to-right), making it perfect for astronomy but unsuitable for terrestrial viewing where correct image orientation is required.\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\"\u003eWhy is a 99% dielectric diagonal like the SVBONY SV188P better than a standard one?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eA 99% dielectric diagonal like the \u003cstrong\u003eSVBONY SV188P\u003c\/strong\u003e transmits more of the light gathered by your telescope to the eyepiece. Standard diagonals can lose 5% or more of the light, but the SV188P loses only 1%. This results in brighter, higher-contrast images, which is especially critical for observing faint deep-sky objects like nebulae and galaxies.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the image orientation through the SVBONY SV188P diagonal?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eThe SVBONY SV188P provides an image that is \u003cstrong\u003eupright but mirror-inverted\u003c\/strong\u003e (left and right are reversed). This is standard for astronomical mirror diagonals and is perfectly fine for observing celestial objects, as there is no \"up\" or \"down\" in space. However, it is not suitable for terrestrial viewing.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the SVBONY SV188P's brass compression ring protect my eyepieces?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eInstead of a single set screw digging into your eyepiece barrel, the SVBONY SV188P uses a \u003cstrong\u003esoft brass compression ring\u003c\/strong\u003e that tightens evenly around the barrel. This provides a secure grip without leaving scratches or gouges, preserving the condition of your valuable eyepieces.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eWill the SVBONY SV188P work with my refractor or SCT?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eYes, the SV188P is designed specifically for telescopes that focus straight through the back, such as \u003cstrong\u003erefractors, Schmidt-Cassegrains (SCTs), and Maksutov-Cassegrains\u003c\/strong\u003e. The 90-degree angle provides a much more comfortable viewing position than looking straight through.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the SV188P's 99% reflectivity help when observing faint details on Jupiter with my 8\" SCT?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eWhen observing planets like Jupiter, maximizing light throughput is key to seeing subtle, low-contrast features. The SVBONY SV188P's \u003cstrong\u003e99% reflectivity\u003c\/strong\u003e ensures that the faintest details in Jupiter's cloud bands and the Great Red Spot are delivered to your eye with maximum brightness and contrast, making them easier to resolve at high magnification.\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n      \u003ch3 class=\"DAV-accordion-Q\"\u003eIs the SVBONY SV188P diagonal suitable for terrestrial viewing, like bird watching?\u003c\/h3\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion-A\"\u003e\n      \u003cp\u003eNo, the SVBONY SV188P is not recommended for terrestrial use. It produces a \u003cstrong\u003emirror-reversed image\u003c\/strong\u003e, meaning text would appear backwards. For correct image orientation for daytime viewing, you would need a 45-degree or 90-degree correct-image prism diagonal.\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\u003eBrand\u003c\/td\u003e\n          \u003ctd\u003eSVBONY\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eMaterial\u003c\/td\u003e\n          \u003ctd\u003eAluminum Alloy\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eCoatings\u003c\/td\u003e\n          \u003ctd\u003eDielectric\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eReflectivity\u003c\/td\u003e\n          \u003ctd\u003e99%\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eReflection Surface\u003c\/td\u003e\n          \u003ctd\u003eDielectrically Coated\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eMirror Thickness\u003c\/td\u003e\n          \u003ctd\u003e11mm\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eImage Orientation\u003c\/td\u003e\n          \u003ctd\u003eErect Image, Mirror Inverted\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eSet Screws\u003c\/td\u003e\n          \u003ctd\u003eM4\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\"\u003eSVBONY SV188P 2\" Dielectric Diagonal\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\"\u003eDust Caps\u003c\/p\u003e\n          \u003cp class=\"DAV-item-subtitle\"\u003e× 2\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\/svbony-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSVBONY 1-Year Warranty\u003c\/a\u003e\n  \u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SVBONY","offers":[{"title":"Default Title","offer_id":52861237526813,"sku":"SV-F9171D","price":88.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/SVBONY-SV188P-99-Reflectivity-90-Degree-Dielectric-Mirror-Diagonal-1-F9171D_86aad769-0b9e-4e84-b1cd-45a2397de09e.jpg?v=1788883456"},{"product_id":"svbony-sv221-90-brass-mirror-diagonal-125in","title":"SVBONY SV221 90° Brass Mirror Diagonal - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e90° Deflection Angle for Comfortable Viewing\u003c\/li\u003e\n\u003cli\u003eAluminum-Coated Mirror with \u0026gt;92% Reflectivity\u003c\/li\u003e\n\u003cli\u003eStandard 1.25\" Barrel and Eyepiece Clamp\u003c\/li\u003e\n\u003cli\u003eAccepts 1.25\" Filters via M28.5x0.6 Threads\u003c\/li\u003e\n\u003cli\u003eBrass Compression Ring Prevents Eyepiece Scratches\u003c\/li\u003e\n\u003cli\u003eLightweight 90.5g 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\u003eSVBONY SV221 1.25\" 90° Brass Diagonal for Refractor Telescope\u003c\/h2\u003e\n\u003cp\u003eThe SVBONY SV221 1.25\" 90° Brass Diagonal redirects the light path of your refractor, providing a comfortable viewing angle for objects high in the sky. Its aluminum-coated mirror has a reflectivity greater than 92% across a 29.5mm clear aperture, ensuring bright images with minimal light loss. The integrated M28.5x0.6 thread allows for the use of standard 1.25\" filters, and at just 90.5g, it adds minimal weight to your optical 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\u003e90° Viewing Angle with \u0026gt;92% Reflectivity\u003c\/h3\u003e\n\u003cp\u003eA 90° diagonal is an essential accessory for any refractor or Schmidt-Cassegrain telescope, eliminating neck strain when observing targets near the zenith. The SVBONY SV221 uses an aluminum-coated mirror with a reflectivity of over 92% to deliver bright, high-contrast views. The 29.5mm clear aperture is large enough to prevent vignetting with standard 1.25\" Plössl eyepieces, preserving the brightness of your telescope's optics. Note that as a mirror diagonal, it provides an image that is vertically correct but horizontally reversed (Erect Image, Mirror Inverted), which is normal for astronomical viewing but not ideal for terrestrial use where correct image orientation is required.\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\u003eBrass Ring Clamp and M28.5x0.6 Filter Threads\u003c\/h3\u003e\n\u003cp\u003eThe SV221 is engineered to protect your equipment while enhancing its capabilities. Unlike basic diagonals that use a single screw to hold the eyepiece, this model features a brass compression ring that provides a secure, non-marring grip on your eyepiece barrels, preventing scratches and gouges. The nosepiece is threaded for standard M28.5x0.6 filters, allowing you to easily add a moon filter or light pollution filter to your setup without needing to thread it onto each individual eyepiece.\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 purpose of the SVBONY SV221 diagonal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe SVBONY SV221 is a \u003cstrong\u003e90° mirror diagonal\u003c\/strong\u003e designed for refractor and Schmidt-Cassegrain telescopes. Its primary purpose is to bend the light path at a right angle, allowing you to observe comfortably, especially when the telescope is pointing towards the zenith (straight up).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the brass pressure ring on the SV221 protect my eyepieces?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe brass compression ring provides a significant advantage over simple set-screw designs. When you tighten the clamp, the soft brass ring gently and evenly squeezes the eyepiece barrel. This holds it securely in place without the screw tip digging into the barrel, which prevents the scratches and gouges common with lower-quality diagonals.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 1.25\" filters with the SVBONY SV221?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The 1.25\" nosepiece of the SVBONY SV221 has standard \u003cstrong\u003eM28.5x0.6 threads\u003c\/strong\u003e. This allows you to screw any standard 1.25\" filter, such as a moon filter or a nebula filter, directly onto the diagonal itself.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the SVBONY SV221 suitable for observing Jupiter with my 80mm refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. The SVBONY SV221 is an excellent choice for planetary viewing with an 80mm refractor. Its \u003cstrong\u003e\u0026gt;92% reflectivity\u003c\/strong\u003e ensures that the bright image of Jupiter (and its moons) reaches your eyepiece with minimal light loss, preserving contrast and detail in the planet's cloud bands. The 90° angle will make observing much more comfortable as Jupiter climbs higher in the sky.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"Erect Image, Mirror Inverted\" mean for the view through the SV221?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis describes the image orientation. \"Erect Image\" means the view is right-side up, but \"Mirror Inverted\" means it is flipped left-to-right. For astronomy, this is perfectly acceptable as there is no \"up\" or \"down\" in space. However, it means that text or terrestrial objects would appear backward, making it less suitable for daytime terrestrial viewing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eI find it difficult to look through my refractor when it's pointed at the zenith. Will the SVBONY SV221 diagonal help?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, this is exactly what the SVBONY SV221 is designed for. By redirecting the light path by \u003cstrong\u003e90°\u003c\/strong\u003e, it allows you to look down into the eyepiece from a comfortable standing or seated position, even when the telescope is aimed directly overhead. This completely solves the issue of having to crouch or kneel to use your refractor.\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\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eSVBONY\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSize\u003c\/td\u003e\n\u003ctd\u003e1.25 inch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eMirror Diagonal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDeflection Angle\u003c\/td\u003e\n\u003ctd\u003e90°\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReflectivity\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;92%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReflection Surface\u003c\/td\u003e\n\u003ctd\u003eAluminum Coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e29.5mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Orientation\u003c\/td\u003e\n\u003ctd\u003eErect Image, Mirror Inverted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLens-Sided Connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" Barrel with M28.5x0.6 Filter Thread\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEyepiece-Sided Connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" Clamp\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClamping System\u003c\/td\u003e\n\u003ctd\u003eBrass Compression Ring with Screw Clamps\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003eapprox. 73mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003ePlastic \u0026amp; Metal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet Weight\u003c\/td\u003e\n\u003ctd\u003e90.5g \/ 3.19oz\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\"\u003eSV221 1.25\" 90 Degree Mirror Diagonal\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\"\u003eM3 Screws\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 3\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\"\u003eDust 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\"\u003eDust Plug\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\/svbony-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSVBONY 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SVBONY","offers":[{"title":"Default Title","offer_id":52861237559581,"sku":"SV-W9178A","price":21.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/SVBONY-SV221-1-25-90-Brass-Diagonal-for-Refractor-Telescope-1_8b7ba08c-cdce-47b8-adc1-807d5a4a713f.jpg?v=1788883600"},{"product_id":"svbony-sv221-45-correct-image-prism-diagonal-125in","title":"SVBONY SV221 45° Correct Image Prism Diagonal - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eProduces a fully erect, non-reversed image\u003c\/li\u003e\n\u003cli\u003eComfortable 45° viewing angle for terrestrial observation\u003c\/li\u003e\n\u003cli\u003eStandard 1.25\" barrel fits most refractor telescopes\u003c\/li\u003e\n\u003cli\u003eFeatures a 19mm clear aperture\u003c\/li\u003e\n\u003cli\u003eThreaded (M28.5x0.6) to accept 1.25\" filters\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\u003eSVBONY SV221 45-Degree Erecting Prism Diagonal for Refractor Telescope\u003c\/h2\u003e\n\u003cp\u003eThe SVBONY SV221 converts your refractor for terrestrial viewing, delivering a fully erect, non-reversed image at a comfortable 45° angle. It fits standard 1.25 inch focusers, features a 19mm clear aperture for bright views, and adds approximately 86mm of optical length to your light path. Weighing only 79g, this multi-coated prism diagonal is threaded for M28.5x0.6 filters, making it a lightweight and versatile addition to your kit.\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\u003eCorrect-Image Views at a Comfortable 45° Angle\u003c\/h3\u003e\n\u003cp\u003eThe primary function of the SV221 is to correct the inverted and reversed image produced by a refractor telescope. Its internal prism system delivers an erect, non-reversed view, just as you see with your naked eye, making it intuitive to track moving subjects like birds, ships, or wildlife. The 45° deflection provides a much more comfortable viewing posture for daytime observation compared to looking straight through the telescope.\u003c\/p\u003e\n\u003cp\u003eThe multi-coated prism and 19mm clear aperture ensure that the image remains bright and clear. This makes the SV221 an essential accessory for transforming your astronomical refractor into a powerful, long-range spotting scope for terrestrial use.\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\u003eSecure Clamping and 1.25\" Filter Compatibility\u003c\/h3\u003e\n\u003cp\u003eThe SV221 is constructed with a durable, precision-molded plastic main body and machined aluminum barrels for a secure fit. Unlike basic diagonals that use a single screw to hold the eyepiece, this model features a brass compression ring that provides a firm, even grip without scratching or marring your eyepiece barrels. This secure connection maintains optical alignment and protects your equipment.\u003c\/p\u003e\n\u003cp\u003eFor added versatility, the 1.25\" nosepiece is threaded for standard M28.5x0.6 filters. You can easily attach a moon filter, a light pollution filter, or colored planetary filters to enhance your views without needing a separate filter cell.\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\u003eSV221 Erecting Prism vs. a Standard Mirror Diagonal\u003c\/h3\u003e\n\u003cp\u003eIt's important to choose the right diagonal for your purpose. While both redirect light for comfortable viewing, they produce very different images.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard Mirror Diagonal:\u003c\/strong\u003e A typical \"star diagonal\" uses a mirror to bend the light path. This produces an image that is upright but reversed left-to-right. This is perfectly acceptable for astronomy, as stars are points of light, but it can be disorienting for terrestrial viewing where \"left is left\" matters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSVBONY SV221 Erecting Prism:\u003c\/strong\u003e This diagonal uses a prism to provide a fully corrected image—upright and not reversed. This is the ideal choice for daytime, terrestrial observation with a refractor or Maksutov-Cassegrain, as it makes panning and tracking objects natural and intuitive.\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\"\u003eWhy do I need the SVBONY SV221 for daytime viewing with my refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA refractor telescope naturally produces an image that is upside-down and backward. The SVBONY SV221 uses a 45° prism to correct this, delivering an \u003cstrong\u003eerect and non-reversed image\u003c\/strong\u003e. This makes it possible to use your astronomy telescope as a high-power spotting scope for activities like birdwatching or landscape viewing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the SVBONY SV221 work with my Newtonian telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The SVBONY SV221 is designed for refractor and Cassegrain-type telescopes. A Newtonian reflector does not have enough focuser travel to reach focus with the additional \u003cstrong\u003e86mm optical length\u003c\/strong\u003e of a prism diagonal. Newtonians require very low-profile focusers and do not typically use diagonals in the same way.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 1.25\" filters with the SVBONY SV221 diagonal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The 1.25\" barrel of the SV221 has standard \u003cstrong\u003eM28.5x0.6 filter threads\u003c\/strong\u003e. This allows you to attach any standard 1.25\" filter, such as a moon filter for reducing glare or a light pollution filter for enhancing contrast on celestial objects.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the advantage of the SVBONY SV221's clamping system?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe SV221 features a brass compression ring inside the eyepiece holder. When you tighten the screw, this ring tightens evenly around the eyepiece barrel. This is superior to a simple screw which can scratch or dent your eyepieces and potentially cause a slight tilt.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the SVBONY SV221 suitable for high-magnification planetary viewing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile the SVBONY SV221 can be used for astronomy, it is primarily optimized for lower-power terrestrial viewing. Prism diagonals can sometimes introduce a small amount of chromatic aberration (false color) at very high magnifications. For critical, high-power observation of planets like Jupiter or Saturn, a high-quality mirror diagonal is often preferred by discerning astronomers.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 45° angle of the SV221 affect observing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003e45° angle\u003c\/strong\u003e is ideal for terrestrial viewing, as you are typically looking at objects at or near the horizon. This provides a comfortable, natural neck position. For astronomical viewing, a 90° diagonal is often preferred, as it makes it easier to view objects that are high overhead, near the zenith.\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\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eSVBONY\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eSV221\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003ePrism Diagonal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBarrel Size\u003c\/td\u003e\n\u003ctd\u003e1.25 inch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDeflection Angle\u003c\/td\u003e\n\u003ctd\u003e45°\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Orientation\u003c\/td\u003e\n\u003ctd\u003eErect image, non-reversed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e19mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eMulti-Coated (MC)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEyepiece Connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" Clamp with Screw\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Threads\u003c\/td\u003e\n\u003ctd\u003eM28.5x0.6\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003eappr. 86mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003ePlastic \u0026amp; Metal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet Weight\u003c\/td\u003e\n\u003ctd\u003e79g \/ 2.78oz\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\"\u003eSV221 1.25\" 45 Degree Correct Image Prism Diagonal\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\"\u003eM3 Screws\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 3\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\"\u003eDust 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\"\u003eDust Plug\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\/svbony-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSVBONY Warranty Policy\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SVBONY","offers":[{"title":"Default Title","offer_id":52861237592349,"sku":"SV-W9178B","price":25.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/SVBONY-SV221-45-Degree-Erecting-Prism-Diagonal-for-Refractor-Telescope-1_1489e9fd-f5d1-483a-8a02-fee8a0ff304d.jpg?v=1788883589"},{"product_id":"svbony-sv222-45-correct-image-prism-diagonal-fmc-125in","title":"SVBONY SV222 45° Correct Image Prism Diagonal FMC - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eProduces an erect, non-reversed image for terrestrial and astronomical viewing\u003c\/li\u003e\n\u003cli\u003e45° deflection angle provides a comfortable viewing position\u003c\/li\u003e\n\u003cli\u003ePhase-coated BK7 prism for enhanced image contrast and brightness\u003c\/li\u003e\n\u003cli\u003eFits standard 1.25-inch focusers and eyepieces\u003c\/li\u003e\n\u003cli\u003eCNC machined aluminum body weighs only 167g\u003c\/li\u003e\n\u003cli\u003eFeatures a 16mm clear aperture and accepts 1.25\" filters (M28.5x0.6)\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\u003eSvbony SV222 1.25\" 45° Correct Image Diagonal FMC Phase Coating\u003c\/h2\u003e\n\u003cp\u003eThe Svbony SV222 1.25\" Correct Image Diagonal uses a 45° BK7 prism to deliver a correctly oriented, non-reversed image suitable for both daytime terrestrial viewing and astronomical observation. Its phase-coated and fully multi-coated optics pass through a 16mm clear aperture, providing high-contrast views with an optical path length of approximately 93mm. The entire CNC-machined aluminum body weighs a mere 167g, adding minimal weight to your refractor or catadioptric telescope setup.\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 45° Erect, Non-Reversed View for Terrestrial and Astro Use\u003c\/h3\u003e\n\u003cp\u003eUnlike a standard 90° star diagonal that produces a mirror-reversed image, the SV222's prism design corrects the view completely. This means left is left and right is right, just as you see with your naked eye. This intuitive orientation is essential for terrestrial applications like birdwatching or landscape viewing, transforming your astronomical telescope into a high-power spotting scope. The 45° viewing angle is more natural for daytime use than a 90° angle, reducing neck strain during extended sessions.\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\u003ePhase-Coated BK7 Prism: Maximizing Contrast with a 16mm Aperture\u003c\/h3\u003e\n\u003cp\u003eThe heart of the SV222 is its BK7 prism, which features both full multi-coatings and advanced phase coatings. Phase correction is a critical treatment that eliminates destructive interference within the prism, resulting in a measurable increase in image contrast and resolution. This allows you to resolve finer details on planets and see fainter stars against a darker sky background. The interior of the diagonal is blackened and baffled to absorb stray light, further enhancing contrast. The 16mm clear aperture is sufficient for most planetary and lunar eyepieces, though it may cause slight vignetting with very long focal length 1.25\" eyepieces that have wide field stops.\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\u003eCNC Aluminum Build with a 1.25\" Non-Marring Brass Clamp\u003c\/h3\u003e\n\u003cp\u003eThe SV222 is built from a single piece of CNC-machined aluminum with a durable anodized finish, ensuring precise optical alignment and longevity. The 1.25\" eyepiece holder uses a brass compression ring instead of a simple screw, which clamps your eyepieces securely without scratching or marring their barrels. The 1.25\" nosepiece is threaded to accept standard M28.5x0.6 filters, allowing you to easily add a moon filter or light pollution filter to your observing chain.\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\"\u003eWhy choose the Svbony SV222 45° diagonal over a standard 90° star diagonal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eChoose the \u003cstrong\u003eSvbony SV222\u003c\/strong\u003e when you need a correctly oriented, non-reversed image. This is essential for daytime terrestrial viewing (birdwatching, nature) where a mirror-image from a standard diagonal would be disorienting. The 45° angle is also often more comfortable for daytime use. For purely astronomical viewing, a 90° diagonal is typically preferred for its more comfortable angle when observing objects high in the sky.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"phase coating\" do on the SV222's prism?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003ePhase coatings\u003c\/strong\u003e correct for a phenomenon called \"phase shift\" that occurs when light is reflected within a prism. This correction prevents destructive light wave interference, resulting in significantly improved image contrast, resolution, and brightness compared to an uncoated prism. It's a premium feature that helps the SV222 deliver sharper views.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Svbony SV222 with my Newtonian reflector telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eNo.\u003c\/strong\u003e The Svbony SV222 has an optical path length of approximately 93mm, which is too long for a standard Newtonian reflector. You will not be able to rack the focuser in far enough to reach focus. This diagonal is designed specifically for refracting and catadioptric (SCT, Maksutov) telescopes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the SV222's 16mm clear aperture cause vignetting with my eyepieces?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003e16mm clear aperture\u003c\/strong\u003e is generally well-matched for most 1.25\" eyepieces used for planetary, lunar, and double star observing. However, you may experience some vignetting (darkening at the edge of the field) if you use a 1.25\" eyepiece with a very long focal length (like a 32mm or 40mm Plössl) that has a field stop larger than 16mm.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Svbony SV222 perform for birdwatching with a small 80mm f\/7 refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003eSvbony SV222\u003c\/strong\u003e is an excellent match for this scenario. It will provide a correctly oriented, high-contrast image, making it easy to follow birds in motion. The 45° angle is comfortable for viewing subjects at or near the horizon, and the phase-coated optics will help resolve fine feather details and subtle color variations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the SV222 a good choice for viewing the Moon and planets with a Maksutov-Cassegrain?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it is a very capable choice. While the 45° angle might be less comfortable than a 90° for objects directly overhead, the phase-coated optics of the \u003cstrong\u003eSvbony SV222\u003c\/strong\u003e will deliver sharp, high-contrast views of lunar craters, Jupiter's cloud bands, and Saturn's rings. The correct-image orientation can also make it easier to navigate the lunar surface using a map.\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\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eSVBONY\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003ePrism Diagonal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrism Material\u003c\/td\u003e\n\u003ctd\u003eBK7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDeflection Angle\u003c\/td\u003e\n\u003ctd\u003e45°\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Orientation\u003c\/td\u003e\n\u003ctd\u003eErect image, non-reversed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBarrel Size\u003c\/td\u003e\n\u003ctd\u003e1.25 inch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e16mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eFully Multi-Coated + Phase Coatings\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003eapprox. 93mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Threads\u003c\/td\u003e\n\u003ctd\u003eM28.5x0.6 (Lens Sided)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEyepiece Connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" Clamp\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClamping System\u003c\/td\u003e\n\u003ctd\u003eBrass Compression Ring with Screw\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBody Material\u003c\/td\u003e\n\u003ctd\u003eCNC Metal Aluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet Weight\u003c\/td\u003e\n\u003ctd\u003e167g \/ 5.87oz\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\"\u003eSV222 1.25\" 45° Metal Correct Image Prism Diagonal\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\"\u003eM4 Screws\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\"\u003eDust 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\"\u003eDust Plug\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\/svbony-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSVBONY Warranty Policy\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SVBONY","offers":[{"title":"Default Title","offer_id":52861237657885,"sku":"SV-W9179A","price":56.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/SVBONY-SV222-1-25-45-Correct-Image-Diagonal-FMC-Phase-Coating-1_2cd5b71e-12ee-4d0e-8e90-43f927cbc48a.jpg?v=1788883612"},{"product_id":"svbony-sv222-90-erect-image-prism-diagonal-125in","title":"SVBONY SV222 90° Erect Image Prism Diagonal - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eProduces a 90° erect, non-reversed image\u003c\/li\u003e\n\u003cli\u003eStandard 1.25-inch barrel size\u003c\/li\u003e\n\u003cli\u003eBK7 prism with anti-reflection coatings\u003c\/li\u003e\n\u003cli\u003e19mm clear aperture\u003c\/li\u003e\n\u003cli\u003eCNC machined aluminum body\u003c\/li\u003e\n\u003cli\u003eThreaded for M28.5x0.6 filters\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\u003eSvbony SV222 1.25\" 90° Erect Prism Diagonal\u003c\/h2\u003e\n\u003cp\u003eThe Svbony SV222 1.25\" 90° Erect Prism Diagonal corrects the view in your refractor or Cassegrain telescope, delivering an upright and non-reversed image essential for terrestrial observation. Its BK7 prism provides a 19mm clear aperture, and the entire CNC-machined aluminum unit adds only 153.8g to your optical train. The optical path length is approximately 65.6mm, and the barrel is threaded to accept standard M28.5x0.6 filters.\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\u003e90° BK7 Prism: Correct Orientation for Land and Sky\u003c\/h3\u003e\n\u003cp\u003eThe core of the SV222 is a BK7 glass prism that deflects light 90°, providing a comfortable viewing angle while producing an \"erect image, non-reversed\" orientation. This is critical for daytime use like birdwatching or landscape viewing, where a standard astronomy diagonal's mirror-reversed image is disorienting. For astronomy, it makes navigating with star charts more intuitive, as the view in the eyepiece matches the chart exactly.\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\u003eCNC Machined Body with a 19mm Clear Aperture\u003c\/h3\u003e\n\u003cp\u003eConstructed from CNC-machined aluminum, the SV222 body is built for durability and precise alignment. The interior is blackened and baffled around the 19mm clear aperture to absorb stray light, preventing internal reflections from reducing image contrast. This ensures a darker background sky and sharper details on both celestial and terrestrial targets.\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\u003eSecure Clamping and M28.5x0.6 Filter-Ready Design\u003c\/h3\u003e\n\u003cp\u003eThe SV222 uses a screw clamp system to securely hold your 1.25\" eyepieces, preventing wobble and maintaining optical alignment. This mechanism provides a firm grip without marring the eyepiece barrel. The 1.25\" nosepiece is threaded for M28.5x0.6 filters, allowing you to easily add a moon filter, light pollution filter, or planetary color filters to enhance your view.\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\u003eSV222 Erecting Prism vs. Standard Mirror Diagonal\u003c\/h3\u003e\n\u003cp\u003eChoosing between an erecting prism and a mirror diagonal depends entirely on your primary use case. Both provide a comfortable 90° viewing angle, but the image orientation is fundamentally different.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSV222 Erecting Prism:\u003c\/strong\u003e Delivers a fully correct image (upright and not reversed left-to-right). This is non-negotiable for terrestrial viewing and highly convenient for beginners learning to navigate the sky with charts.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard Mirror Diagonal:\u003c\/strong\u003e Produces an image that is upright but reversed left-to-right. For purely astronomical deep-sky observing, a high-quality dielectric mirror diagonal may offer slightly higher light transmission, though the SV222's anti-reflection coatings deliver bright, high-contrast images suitable for all-around use.\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\"\u003eWhy do I need an erect image diagonal like the SVBONY SV222 for my refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA refractor or SCT naturally produces an image that is upside-down and reversed. A standard star diagonal corrects the up-down orientation but leaves it mirror-reversed. The \u003cstrong\u003eSVBONY SV222\u003c\/strong\u003e is an erecting prism that corrects both, delivering a view that is upright and correctly oriented left-to-right, just as you see with your naked eye. This is essential for daytime terrestrial viewing and makes astronomical navigation with star charts much more intuitive.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the SVBONY SV222 for observing planets like Jupiter in my 8\" SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, absolutely. The SV222 is a great choice for planetary viewing in a Schmidt-Cassegrain or refractor. Its anti-reflection coated BK7 prism provides sharp, high-contrast images, allowing you to resolve details like Jupiter's cloud bands or Saturn's rings. The correct image orientation can also make it easier to track the planet's movement across the sky.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the SV222 a good choice for birdwatching with an 80mm refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe SV222 is an ideal choice for this application. Its primary function is to provide a correctly oriented image, which is exactly what you need for terrestrial use like birdwatching. The 90° angle is comfortable for viewing subjects at various elevations, and the all-metal construction ensures it can handle field use.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the difference between this SV222 prism diagonal and a mirror diagonal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe main difference is the image orientation. The \u003cstrong\u003eSV222 prism diagonal\u003c\/strong\u003e provides a fully corrected, non-reversed image. A \u003cstrong\u003emirror diagonal\u003c\/strong\u003e provides an image that is right-side-up but reversed left-to-right. For terrestrial viewing, the prism is necessary. For astronomy, it's a matter of preference; some purists prefer high-end mirror diagonals for maximum light transmission on faint deep-sky objects, while many find the prism's correct view more convenient.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the SVBONY SV222 accept 1.25\" astronomy filters?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The 1.25\" nosepiece that inserts into your telescope's focuser is threaded with a standard \u003cstrong\u003eM28.5x0.6 thread\u003c\/strong\u003e. This allows you to attach any standard 1.25\" filter, such as a moon filter, a light pollution filter, or colored planetary filters.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the SV222 correct the image in a Newtonian telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. This diagonal is designed for refractors, Maksutov-Cassegrains, and Schmidt-Cassegrains. Newtonian reflectors have a different optical design and typically do not have enough focus travel to accommodate a prism diagonal. You would not be able to reach focus with the SV222 in a standard Newtonian.\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\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eSVBONY\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eSV222\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSize\u003c\/td\u003e\n\u003ctd\u003e1.25 inch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e90° Prism Diagonal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrism Material\u003c\/td\u003e\n\u003ctd\u003eBK7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Orientation\u003c\/td\u003e\n\u003ctd\u003eErect image, non-reversed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDeflection Angle\u003c\/td\u003e\n\u003ctd\u003e90°\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e19mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoating\u003c\/td\u003e\n\u003ctd\u003eAnti-reflection coating\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBody Material\u003c\/td\u003e\n\u003ctd\u003eCNC Metal Aluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClamping System\u003c\/td\u003e\n\u003ctd\u003eScrew clamps\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEyepiece Side Connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" Clamp\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Side Connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" Barrel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thread\u003c\/td\u003e\n\u003ctd\u003eM28.5x0.6\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003eappr. 65.6mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet Weight\u003c\/td\u003e\n\u003ctd\u003e153.8g \/ 5.43oz\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\"\u003eSV222 1.25\" 90° Metal Correct Image Prism Diagonal\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\"\u003eM4 Screws\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\"\u003eDust 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\"\u003eDust Plug\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\/svbony-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSVBONY 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SVBONY","offers":[{"title":"Default Title","offer_id":52861237756189,"sku":"SV-W9179B","price":91.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/SVBONY-SV222-1-25-90-Erect-Prism-Diagonal-AR-Coating-Metal-Mount-1_987b12dc-40aa-494c-9004-844259ce7c79.jpg?v=1788883625"},{"product_id":"svbony-sv223-90-clicklock-dielectric-mirror-diagonal-125in","title":"SVBONY SV223 90° ClickLock Dielectric Mirror Diagonal - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReflects over 99% of incoming light with a lab-tested dielectric coating\u003c\/li\u003e\n\u003cli\u003eFeatures a 1.25\" Clicklock mechanism for fast, secure eyepiece changes\u003c\/li\u003e\n\u003cli\u003eProvides a comfortable 90° viewing angle for refractors and SCTs\u003c\/li\u003e\n\u003cli\u003e25mm clear aperture minimizes vignetting with low-power 1.25\" eyepieces\u003c\/li\u003e\n\u003cli\u003eAccepts standard 1.25\" filters with M28.5x0.6 threads\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\u003eSvbony SV223 1.25\" 90° Clicklock Dielectric Diagonal Mirror\u003c\/h2\u003e\n\u003cp\u003eThe Svbony SV223 1.25\" 90° Clicklock Dielectric Diagonal Mirror combines a lab-tested dielectric mirror with \u0026gt;99% reflectivity and a secure Clicklock clamping system. This design directs the maximum amount of light from your telescope to your eyepiece through its 25mm clear aperture, providing brighter, higher-contrast views than standard diagonals. The robust metal body adds only 249g to your optical train while ensuring your eyepieces are held with absolute stability.\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\u003eThe SV223's \u0026gt;99% Reflectivity Dielectric Mirror\u003c\/h3\u003e\n\u003cp\u003eAt the core of the SV223 is a precision 11.5mm thick optical flat mirror with a multi-layer dielectric coating. This advanced coating achieves over 99% reflectivity across the visual spectrum, preventing the light loss common in standard aluminum or silver-coated diagonals. The result is a tangible increase in image brightness and contrast, allowing you to resolve finer details on planets and detect fainter stars in clusters.\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\u003eInstant Security: The 1.25\" Clicklock Clamping System\u003c\/h3\u003e\n\u003cp\u003eFumbling with small thumbscrews in the dark is eliminated with the SV223's Clicklock mechanism. A simple twist of the outer ring engages a three-point clamp, securely centering and locking your 1.25\" eyepiece or accessory in place without marring the barrel. This system provides a solid, repeatable connection that maintains perfect alignment, critical for high-magnification planetary viewing or imaging.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFast Clamping Action:\u003c\/strong\u003e Lock or release any 1.25\" accessory in seconds with a gentle twist, even while wearing gloves.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDamage-Free Design:\u003c\/strong\u003e The internal compression ring grips the eyepiece barrel evenly, avoiding the scratches and dents caused by single thumbscrews.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBaffled Interior:\u003c\/strong\u003e The metal housing is internally baffled and blackened to absorb stray light, further enhancing image contrast by preventing internal reflections.\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\u003eSV223 Dielectric vs. Standard Diagonals: A Clear Upgrade\u003c\/h3\u003e\n\u003cp\u003eCompared to a standard prism or aluminum-coated mirror diagonal, the SV223 offers a significant step up in optical and mechanical stability. While a standard diagonal might reflect 88-92% of light, the SV223's \u0026gt;99% dielectric coating delivers a noticeably brighter image at the eyepiece.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard Aluminum Mirror:\u003c\/strong\u003e Typically has lower reflectivity and is prone to degradation over time, reducing brightness and contrast. The SV223's dielectric coating is far more durable and maintains its reflectivity for years.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrism Diagonal:\u003c\/strong\u003e Can introduce chromatic aberration in fast telescopes (below f\/7), whereas the SV223 mirror is color-neutral at any focal ratio.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThumbscrew Clamp:\u003c\/strong\u003e A single thumbscrew can cause eyepiece tilt and damage barrels. The SV223's Clicklock ensures perfect centering and a secure, damage-free grip every time.\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 advantage of the SV223's Clicklock system?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary advantage of the \u003cstrong\u003eClicklock clamping system\u003c\/strong\u003e is its ability to securely and perfectly center any 1.25\" eyepiece with a simple twist. This eliminates the risk of eyepiece tilt that can occur with single-thumbscrew diagonals and prevents scratches or dents on your eyepiece barrels.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the SV223's \u0026gt;99% reflectivity affect views of Jupiter in my 8\" SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn an 8\" SCT, the SV223's \u0026gt;99% reflectivity provides a visibly brighter image of Jupiter compared to a standard diagonal with ~90% reflectivity. This increased light throughput enhances the contrast of subtle features like the Great Red Spot (GRS) and delicate cloud bands, making them easier to resolve at high magnification.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs a dielectric mirror like the one in the SV223 better than a prism diagonal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFor most telescopes, especially \"fast\" refractors or Newtonians (f\/7 or lower), a dielectric mirror diagonal like the SV223 is superior. It introduces zero chromatic aberration (false color), unlike a prism which can create color fringing on bright objects in fast optical systems. The SV223's mirror design ensures color-pure images regardless of your telescope's focal ratio.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 1.25\" filters with the Svbony SV223 diagonal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The 1.25\" nosepiece of the SV223 diagonal has standard \u003cstrong\u003eM28.5x0.6 threads\u003c\/strong\u003e, allowing you to attach any 1.25\" astronomical filter, such as a moon filter, light pollution filter, or planetary color filters.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the SV223's 25mm clear aperture cause vignetting with my 32mm Plössl eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. A 32mm Plössl eyepiece has a field stop of approximately 27mm, but since it is placed after the diagonal, the diagonal's \u003cstrong\u003e25mm clear aperture\u003c\/strong\u003e is sufficient to fully illuminate the field of view without causing vignetting. It is well-matched for all standard 1.25\" eyepiece designs.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the optical length of the SV223 and why does it matter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe SV223 has an \u003cstrong\u003eoptical length of approximately 85.5mm\u003c\/strong\u003e. This is the amount of light path it adds to your telescope's focal plane. This is a standard length for 1.25\" diagonals and should allow most refractors and SCTs to reach focus without issue. However, for some Newtonians not designed for visual use, you may need to check your focuser's travel range.\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\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eSVBONY\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eSV223\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSize\u003c\/td\u003e\n\u003ctd\u003e1.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDeflection Angle\u003c\/td\u003e\n\u003ctd\u003e90°\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eMirror Diagonal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReflectivity\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;99%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReflection Surface\u003c\/td\u003e\n\u003ctd\u003eDielectrically Coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e25mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClamping System\u003c\/td\u003e\n\u003ctd\u003eClicklock\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Threads (Lens Side)\u003c\/td\u003e\n\u003ctd\u003eM28.5x0.6\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEyepiece Connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" Clamp\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Connection\u003c\/td\u003e\n\u003ctd\u003e1.25\" Barrel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Orientation\u003c\/td\u003e\n\u003ctd\u003eErect image, Mirror Inverted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003eapprox. 85.5mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMirror Thickness\u003c\/td\u003e\n\u003ctd\u003e11.5mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003eMetal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet Weight\u003c\/td\u003e\n\u003ctd\u003e249g \/ 8.78oz\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\"\u003eSV223 1.25\" 90° Clicklock Dielectric Diagonal Mirror\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\"\u003eM4 Screw\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\"\u003eDust Cap (Eyepiece Side)\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\"\u003eDust Plug (Barrel Side)\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\u003cp\u003eThis accessory does not require software or a dedicated manual for operation.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/svbony-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSVBONY 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SVBONY","offers":[{"title":"Default Title","offer_id":52861237788957,"sku":"SV-W9180A","price":130.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/SVBONY-SV223-1-25-90-Clicklock-Dielectric-Diagonal-Mirror-1_8c17c21e-19dd-4563-a0d2-a665fb600186.jpg?v=1788883638"},{"product_id":"svbony-sv223-90-clicklock-dielectric-mirror-diagonal-2in","title":"SVBONY SV223 90° ClickLock Dielectric Mirror Diagonal - 2\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eFeatures a 2-inch barrel with a \u0026gt;99% reflectivity dielectric mirror\u003c\/li\u003e\n\u003cli\u003eConvenient Clicklock clamping mechanism for secure eyepiece attachment\u003c\/li\u003e\n\u003cli\u003eDeflects light at a 90° angle for comfortable viewing\u003c\/li\u003e\n\u003cli\u003eIncludes a 2-inch to 1.25-inch adapter for wide accessory compatibility\u003c\/li\u003e\n\u003cli\u003eNosepiece is threaded for standard M48x0.75 2-inch filters\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\u003eSvbony SV223 2\" 90° Clicklock Dielectric Telescope Diagonal\u003c\/h2\u003e\n\u003cp\u003eThe Svbony SV223 diagonal combines a high-efficiency optical system with a modern clamping mechanism, delivering bright, high-contrast images through a secure, non-marring interface. Its dielectric mirror provides greater than 99% reflectivity across the visual spectrum, while the 11.5mm thick mirror substrate ensures thermal and mechanical stability. A generous 43mm clear aperture minimizes vignetting with wide-field 2-inch eyepieces, and the entire optical path is housed within a rigid metal body with an optical length of approximately 109.1mm.\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\u003e\u0026gt;99% Reflectivity from a 11.5mm Thick Dielectric Mirror\u003c\/h3\u003e\n\u003cp\u003eAt the core of the SV223 is a dielectric-coated mirror engineered for maximum light throughput. With a measured reflectivity of over 99%, it transmits nearly all collected light to your eyepiece, resulting in brighter views of faint deep-sky objects and higher contrast on planetary surfaces. The 11.5mm thick mirror provides a rigid, stable optical surface that resists flexure and maintains flatness for sharp, detailed images.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDielectric Coatings:\u003c\/strong\u003e Unlike standard aluminum or silver coatings that can degrade over time, dielectric layers are highly durable and maintain their \u0026gt;99% reflectivity for years of use.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-Contrast Baffling:\u003c\/strong\u003e The interior of the diagonal is machined with anti-reflection baffling to absorb stray light, ensuring a dark background sky and improving contrast during lunar and planetary observation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e43mm Clear Aperture:\u003c\/strong\u003e The large clear aperture prevents the light cone from being clipped, fully illuminating the field stop of even the widest 2-inch eyepieces.\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\u003eThe SV223 Clicklock System: Secure, Centered Clamping\u003c\/h3\u003e\n\u003cp\u003eThe Clicklock mechanism replaces traditional thumbscrews with a fast, secure, and self-centering clamping system. A simple twist of the knurled ring locks or unlocks your eyepiece, applying even pressure around the barrel for a solid connection that eliminates wobble and protects your accessories from scratches.\u003c\/p\u003e\n\u003cp\u003eThis system is especially useful for imagers and visual observers who frequently change eyepieces or cameras. The brass compression ring ensures a firm grip without marring the eyepiece barrel, preserving the value and condition of your equipment. An internal safety stop also prevents long eyepiece barrels from making contact with the mirror surface.\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\u003eM48 Threads and 1.25-inch Adapter for Full System Integration\u003c\/h3\u003e\n\u003cp\u003eThe Svbony SV223 is designed for broad compatibility with modern telescope systems. The 2-inch nosepiece features standard M48x0.75 filter threads, allowing you to attach nebula, light pollution, or color filters directly to the diagonal for system-wide filtration.\u003c\/p\u003e\n\u003cp\u003eFor observers with a mixed collection of eyepieces, the included 2-inch to 1.25-inch adapter provides seamless integration. This heavy-duty adapter also uses a non-marring brass compression ring, extending the same protection to your 1.25-inch accessories. The 90° viewing angle provides a comfortable observing position, reducing neck strain when viewing objects high in the sky.\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\u003eSvbony SV223 vs. Baader Clicklock: A Comparative Look\u003c\/h3\u003e\n\u003cp\u003eThe Baader Planetarium 2\" ClickLock diagonal is the established benchmark for this type of accessory, known for its exceptional German-made optical and mechanical precision. The Svbony SV223 adopts the same core concepts—a dielectric mirror and a twist-lock clamping mechanism—to offer a similar user experience at a more accessible price point.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompetitor Advantage (Baader):\u003c\/strong\u003e Baader diagonals typically specify a higher optical surface flatness (e.g., 1\/10λ) and are manufactured to extremely tight tolerances, which can provide a slight edge in image sharpness at very high magnifications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis Product's Advantage (Svbony SV223):\u003c\/strong\u003e The SV223 provides the key functional benefits of a Clicklock system and a \u0026gt;99% reflective dielectric mirror, making it a significant upgrade over standard diagonals. For most visual applications, it delivers comparable brightness and convenience for a fraction of the cost of the premium alternative.\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 SV223's Clicklock system over thumbscrews?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Clicklock system on the Svbony SV223 provides a more secure, self-centering grip on your eyepieces. Unlike thumbscrews that can cause tilt and scratch the barrel, the Clicklock's brass compression ring applies uniform pressure with a simple twist, ensuring perfect alignment and protecting your accessories from damage.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the \u0026gt;99% reflectivity of the SV223 help when viewing the Orion Nebula (M42)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA standard aluminum diagonal might reflect only 88-92% of the light. The Svbony SV223's \u0026gt;99% reflectivity dielectric mirror transmits significantly more of the faint light from M42 to your eye. This results in a brighter image, allowing you to see more of the faint, extended nebulosity and potentially resolve finer detail within the Trapezium star cluster.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Svbony SV223 diagonal work with my 8\" SCT and 2\" eyepieces?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the SV223 is an excellent choice for a Schmidt-Cassegrain Telescope (SCT). It fits directly into the 2-inch visual back of most SCTs and its 43mm clear aperture is large enough to prevent vignetting with wide-field 2-inch eyepieces. The 90° angle is ideal for the comfortable viewing posture required with an SCT on an equatorial mount.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"mirror inverted\" mean for the SV223's image orientation?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe SV223 produces an image that is correctly oriented up-and-down (erect image) but is reversed left-to-right (mirror inverted). This is normal for all mirror diagonals and is perfectly fine for astronomical viewing, as there is no \"correct\" left or right in space. However, it is not ideal for terrestrial viewing where you need a fully corrected image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2\" filters with the Svbony SV223 diagonal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The 2-inch nosepiece of the SV223 that inserts into your telescope's focuser is threaded with standard M48x0.75 threads. This allows you to screw in any standard 2-inch astronomy filter, such as a UHC or O-III filter for nebula viewing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the included 1.25\" adapter on the SV223 also non-marring?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the 2-inch to 1.25-inch adapter included with the SV223 also features a brass compression ring. This ensures that both your 2-inch and 1.25-inch eyepieces are protected from the scratches and gouges that can be caused by traditional set-screw designs.\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\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eSVBONY\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eSV223\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003e90° Mirror Diagonal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBarrel Size\u003c\/td\u003e\n\u003ctd\u003e2-inch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClear Aperture\u003c\/td\u003e\n\u003ctd\u003e43mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReflectivity\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;99%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReflection Surface\u003c\/td\u003e\n\u003ctd\u003eDielectrically Coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMirror Thickness\u003c\/td\u003e\n\u003ctd\u003e11.5mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClamping System\u003c\/td\u003e\n\u003ctd\u003eClicklock\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEyepiece Side Connection\u003c\/td\u003e\n\u003ctd\u003e2-inch Clamp\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Side Connection\u003c\/td\u003e\n\u003ctd\u003e2-inch Barrel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Threads\u003c\/td\u003e\n\u003ctd\u003eM48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003eapprox. 109.1mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Orientation\u003c\/td\u003e\n\u003ctd\u003eErect image, Mirror Inverted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003eMetal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet Weight\u003c\/td\u003e\n\u003ctd\u003e573.7g (20.24oz)\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\"\u003eSV223 2\" 90° Clicklock Dielectric Diagonal Mirror\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\"\u003e2\" to 1.25\" Adapter\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\"\u003eM4 Screws\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\"\u003eDust 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\"\u003eDust Plug\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\/svbony-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSvbony 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SVBONY","offers":[{"title":"Default Title","offer_id":52861237821725,"sku":"SV-W9180B","price":151.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/SVBONY-SV223-2-90-Clicklock-Dielectric-Telescope-Diagonal-1_2c9fe056-b1cd-4aa4-b004-7842daefb1a0.jpg?v=1788883648"}],"url":"https:\/\/davidastro.com\/fr\/collections\/svbony-diagonals.oembed","provider":"David Astro","version":"1.0","type":"link"}