{"product_id":"svbony-sv197-cheshire-collimating-eyepiece","title":"SVBONY SV197 1.25″ Cheshire Collimating Eyepiece for Newtonians","description":"\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385872182173339519705406.jpg?v=1791669930\" alt=\"SVBONY SV197 1.25 inch Cheshire collimating eyepiece key visual\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe SVBONY SV197 is a 1.25″ Cheshire collimating eyepiece for aligning the mirrors of a Newtonian reflector. It combines a sight tube with steel crosshairs and a reflective Cheshire face, so you can centre the secondary mirror under the focuser and then adjust the primary until its reflection is centred. The body is CNC-machined aluminium, black oxidised, measures 141 × 41 × 32 mm and weighs 156 g.\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/w9154a-2_20250807114457_5969.jpg?v=1791670427\" alt=\"SVBONY SV197 Cheshire collimating eyepiece crosshair and sight tube\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you own a Newtonian or Dobsonian and want a passive collimation tool that needs no batteries and does not depend on the focuser's own alignment the way a laser can.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSteel crosshairs\u003c\/strong\u003e for centring the secondary and primary reflections.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.25″ (31.75 mm) barrel\u003c\/strong\u003e for 1.25″ focusers or 2″ adapters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCNC aluminium body\u003c\/strong\u003e, black oxidised, with an inner structure that reduces stray reflections.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eNo batteries or electronics.\u003c\/strong\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385872220150846934210861.jpg?v=1791669930\" alt=\"SVBONY SV197 Cheshire eyepiece in a 1.25 inch focuser\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eRoutine collimation\u003c\/strong\u003e of Newtonian and Dobsonian telescopes before an observing or imaging session.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eChecking alignment after transport.\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eVerifying a laser collimator's result.\u003c\/strong\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385872222945862758631936.jpg?v=1791669930\" alt=\"SVBONY SV197 Cheshire collimation view for Newtonian telescopes\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTelescope type:\u003c\/strong\u003e Newtonian reflectors, as SVBONY specifies.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocuser:\u003c\/strong\u003e 1.25″ directly; 2″ focusers with a 2″-to-1.25″ adapter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFast and slow scopes:\u003c\/strong\u003e SVBONY notes that on fast telescopes (around f\/5 and faster) the correctly collimated view sits slightly off-centre, while on slower telescopes it is more centred and easier to read.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/w9154a-3_20250807114457_6462.jpg?v=1791670427\" alt=\"SVBONY SV197 Cheshire collimating eyepiece side view\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/w9154a-4_20250807114457_7013.jpg?v=1791670427\" alt=\"SVBONY SV197 Cheshire collimating eyepiece reflective face\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDaylight or a lit room helps:\u003c\/strong\u003e a Cheshire relies on ambient light entering its side port to illuminate the reflective face.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eNet weight 156 g.\u003c\/strong\u003e\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\u003eIt slides into the focuser like an eyepiece. Collimation itself takes a little practice: centre the secondary under the crosshair, then turn the primary adjusting screws until the primary's reflection sits centred in the secondary.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo I need batteries?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo. It is a passive optical tool.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes it work on refractors or SCTs?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eSVBONY lists it for Newtonian telescopes.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: a 1.25″ CNC aluminium Cheshire collimating eyepiece with steel crosshairs, for centring the secondary and primary mirrors of a Newtonian without batteries or electronics.\u003c\/p\u003e","brand":"SvBony","offers":[{"title":"Default Title","offer_id":67722292527215,"sku":"W9154A","price":34.16,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/w9154a-0_20251231153428_5592.webp?v=1791670426","url":"https:\/\/ontariotelescope.com\/products\/svbony-sv197-cheshire-collimating-eyepiece","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}