{"product_id":"svbony-sv188p-1-25-dielectric-mirror-diagonal","title":"SVBONY SV188P 1.25″ 90° Dielectric Mirror Diagonal","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe SVBONY SV188P is a 1.25″ 90° star diagonal with a dielectric-coated mirror rated at 99% reflectivity. The aluminium-alloy body has a 1.25″ nosepiece with an M28.5 x 0.6 filter thread and a 1.25″ eyepiece clamp with a brass compression ring and brass thumbscrew. The mirror is 11 mm thick, and the diagonal weighs 125 g.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you observe through a refractor, Maksutov or SCT and want a comfortable viewing position for objects high in the sky, with a bright, high-reflectivity mirror in the light path.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e99% reflectivity dielectric mirror:\u003c\/strong\u003e bright images with minimal light loss.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e90° viewing angle:\u003c\/strong\u003e comfortable posture when the telescope points high.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrass compression ring and thumbscrew:\u003c\/strong\u003e holds the eyepiece securely without scratching the barrel or letting it rotate.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM28.5 x 0.6 filter thread\u003c\/strong\u003e on the nosepiece for standard 1.25″ filters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAluminium alloy body\u003c\/strong\u003e with M4 set screws.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisual observing\u003c\/strong\u003e of the Moon, planets, double stars and deep-sky objects.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eComfortable high-altitude viewing\u003c\/strong\u003e with refractors and catadioptric telescopes.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eNosepiece:\u003c\/strong\u003e 1.25″ barrel, fits any 1.25″ focuser or visual back.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepiece side:\u003c\/strong\u003e 1.25″ clamp.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFilters:\u003c\/strong\u003e M28.5 x 0.6 thread on the nosepiece.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaksutov and SCT use:\u003c\/strong\u003e these telescopes need a 1.25″ visual back. The SVBONY MK127 includes its SCT-to-1.25″ adapter, so the SV188P slides straight in.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eImage orientation:\u003c\/strong\u003e like all mirror diagonals, the view is upright but reversed left to right, which is standard for astronomical observing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e this listing is the 1.25″ version. 2″ eyepieces need a 2″ diagonal.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo. Slide the nosepiece into the focuser or visual back, tighten the set screw, and insert a 1.25″ eyepiece into the brass compression ring.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy a dielectric mirror?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eA dielectric coating reflects 99% of visible light, more than a standard aluminized mirror, which gives a slightly brighter image.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill it work on a Maksutov such as the MK127?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYes, through the telescope's SCT-to-1.25″ adapter.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: a 1.25″ 90° diagonal with a 99% reflectivity dielectric mirror and a brass compression clamp, for bright, comfortable visual observing.\u003c\/p\u003e","brand":"SvBony","offers":[{"title":"Default Title","offer_id":67720868855919,"sku":"F9171D","price":61.55,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/f9171d-1_20251124095503_3109.webp?v=1791651491","url":"https:\/\/ontariotelescope.com\/products\/svbony-sv188p-1-25-dielectric-mirror-diagonal","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}