{"product_id":"nebula-filter-s-ii-2-inch-12nm","title":"Nebula Filter S-II 2-inch 12nm","description":"\u003cp\u003eStreet lights brighten the sky over every town, and in an image that glow lands on the sensor along with the nebula. The Explore Scientific S-II filter passes only \u003cstrong\u003ethe emission line of ionized sulfur at 672 nm, in a 12 nm passband\u003c\/strong\u003e, and absorbs almost all artificial light, so the sulfur emission of emission nebulae, planetary nebulae and supernova remnants records even under a brightened sky.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch5 id=\"key-features\"\u003eKey Features\u003c\/h5\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFor the camera, not the eyepiece.\u003c\/strong\u003e Ionized sulfur glows at 672 nm, in the deep red, where the dark-adapted eye is about 1\/8,000 as sensitive as at its peak. Through an eyepiece this filter shows little or nothing. With a camera it is the sulfur channel of narrowband imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIonized sulfur line at 672 nm.\u003c\/strong\u003e Passes the S-II emission line and absorbs the other emission lines.\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003e12 nm passband.\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eAbsorbs almost all artificial light.\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2-inch size\u003c\/strong\u003e, for 2-inch filter holders and imaging trains.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndividual test report.\u003c\/strong\u003e Each filter ships with its own test sheet, carrying its serial number and measured transmission curve.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch5 id=\"ideal-for\"\u003eIdeal For\u003c\/h5\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eNarrowband imagers\u003c\/strong\u003e building a sulfur, hydrogen-alpha and oxygen set. The \u003ca href=\"\/products\/nebula-filter-h-alpha-2-inch-12nm\"\u003eNebula Filter H-Alpha 2-inch 12nm\u003c\/a\u003e is the matching hydrogen-alpha filter in this size and passband.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImagers under suburban skies\u003c\/strong\u003e, where the narrow passband keeps most of the sky glow off the sensor.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSmaller imaging trains:\u003c\/strong\u003e the same filter comes in the 1.25-inch size as the \u003ca href=\"\/products\/nebula-filter-s-ii-1-25-inch-12nm\"\u003eNebula Filter S-II 1.25-inch 12nm\u003c\/a\u003e.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":67651476947118,"sku":"310110","price":249.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0620\/2494\/1742\/files\/310110_1.jpg?v=1791494521","url":"https:\/\/astrotelescopium.com\/products\/nebula-filter-s-ii-2-inch-12nm","provider":"AstroTelescopium","version":"1.0","type":"link"}