{"product_id":"svbony-sv220-2-3nm-h-alpha-oiii-dual-narrowband-filter","title":"SVBONY SV220 2″ 3nm H-Alpha \u0026 OIII Dual Narrowband Filter","description":"\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/w9198b_20250828175857_7509.jpg?v=1791669965\" alt=\"SVBONY SV220 2 inch 3nm H-alpha and OIII narrowband filter 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 SV220 2″ 3nm is a dual narrowband filter with 3 ±1 nm passbands on OIII (500.7 nm) and H-alpha (656.3 nm), average peak transmittance of 85% or more in both bands, and average OD5 blocking from 300 to 1050 nm. The 2.0 mm substrate has a 44 mm clear aperture, 60\/40 surface quality, transmitted wavefront PV ≤ λ\/4 and 30″ parallelism, mounted in a 6061T aluminium cell (Φ50.8 x 7 mm) with a single M48 x 0.75 male thread. Net weight is 12.5 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 image emission nebulae with a large-sensor colour or mono camera, up to full frame, from a light-polluted site and want the contrast of 3 nm passbands across the whole field.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e3 nm H-alpha and OIII passbands:\u003c\/strong\u003e isolate the emission lines tightly for high contrast under bright skies.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e≥85% average peak transmittance:\u003c\/strong\u003e keeps integration times practical.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMinimal-halo multi-layer coating:\u003c\/strong\u003e reduces glare and halos around bright stars for cleaner colour.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e44 mm clear aperture:\u003c\/strong\u003e SVBONY rates it full-frame compatible and suitable for ultra-wide-angle lenses with reduced vignetting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard 2″ cell:\u003c\/strong\u003e M48 x 0.75 thread.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/w9198b-1_20250828175909_6166.jpg?v=1791669965\" alt=\"SVBONY SV220 2 inch 3nm filter minimal halo coating\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eNarrowing each passband to 3 nm keeps the nebula's line emission while admitting less than half the sky background of a 7 nm filter, so the background darkens and the target stands out. The multi-layer coating is designed to minimise the reflections between filter and sensor that cause halos around bright stars, a common issue with narrowband filters. The 44 mm aperture gives even illumination across a full-frame sensor.\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/w9198b-2_20250828175916_5411.jpg?v=1791669965\" alt=\"SVBONY SV220 2 inch 3nm filter full-frame and wide-angle compatibility\" 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\u003eLarge emission nebulae on full-frame and APS-C sensors\u003c\/strong\u003e from urban and suburban sites.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMoonlit nights:\u003c\/strong\u003e narrow passbands extend usable imaging time.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBicolour Ha\/OIII imaging\u003c\/strong\u003e with a colour camera, or combined data with a mono camera.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/w9198b-3_20250828175937_5948.jpg?v=1791669965\" alt=\"SVBONY SV220 2 inch 3nm filter feature panel\" 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\/w9198b-4_20250905182837_1375.jpg?v=1791669965\" alt=\"SVBONY SV220 2 inch 3nm filter detail panel\" 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\u003eMounting:\u003c\/strong\u003e M48 x 0.75 male thread for 2″ nosepieces, filter drawers, filter wheels and M48 imaging trains.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSensors:\u003c\/strong\u003e 44 mm clear aperture, full-frame compatible per SVBONY.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOptics:\u003c\/strong\u003e tight passbands are best matched to moderate focal ratios. Send us your telescope and camera and we will confirm the fit.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/w9198b-5_20250828175955_8446.jpg?v=1791669965\" alt=\"SVBONY SV220 2 inch 3nm filter M48 thread and cell\" 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\/w9198b-6_20250828180002_5087.jpg?v=1791669965\" alt=\"SVBONY SV220 2 inch 3nm filter specifications panel\" 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\u003eImaging filter:\u003c\/strong\u003e it has no application in visual observing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEmission targets:\u003c\/strong\u003e galaxies and reflection nebulae gain little from narrowband filtering.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExposure:\u003c\/strong\u003e 3 nm passbands call for longer sub-exposures than a 7 nm filter on the same target.\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. It threads onto any M48 x 0.75 nosepiece, drawer or wheel like a standard 2″ filter.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill it cover a full-frame sensor?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eSVBONY specifies it as full-frame compatible, with a 44 mm clear aperture.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003e3 nm or 7 nm?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e3 nm gives higher contrast under bright skies; 7 nm collects signal faster and is more forgiving on very fast optics.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: a 2″ 3 nm H-alpha and OIII dual narrowband filter with a 44 mm full-frame aperture, minimal-halo coating and OD5 blocking for high-contrast nebula imaging from bright skies.\u003c\/p\u003e","brand":"SvBony","offers":[{"title":"Default Title","offer_id":67722305667183,"sku":"W9198B","price":356.24,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/sv220-w9198b-0_20251125105032_6111.webp?v=1791670479","url":"https:\/\/ontariotelescope.com\/products\/svbony-sv220-2-3nm-h-alpha-oiii-dual-narrowband-filter","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}