{"product_id":"optolong-photometric-ubvrcic-filters","title":"Optolong Photometric UBVRcIc Filters","description":"\u003ch1\u003e Optolong Photometric UBVRcIc Filters \u003c\/h1\u003e\n\u003cdiv class=\"prose\"\u003e\n\u003cp\u003e\u003cstrong\u003e1. Photometric Filters \u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\"Historically our Solid-State Photometers used custom filters designed to transform well to the Johnson photometry standards with our detectors.\"\u003c\/p\u003e\n\u003cp\u003eUBVRI filters are not for astrophotography. In fact, they are used to do photometry. So it’s in a more scientific application. In photometry, you measure the light coming from a star. By calibrating the data with reference stars, we’re able to get precise measurements on the flux coming out of a star. Combined with a measurement of the distance of the star (that is usually found by satellite to have precise measurements of far stars), we’re able to find fundamental parameters of the stars. Those fundamental parameters are usually the mass, the radius and the temperature of the star.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eMain Use and Performance\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eUBVRcIc filters are not for astrophotography.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWARNING:\u003c\/strong\u003e The filters of Optolong are not designed for sun observation. DO NOT LOOK AT THE SUN WITH OPTOLONG FILTER. You would be BLIND if you fail to observe the warning.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003eOptical glass fine material\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eSpectrum: 300-1000nm\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eSurface Quality: 60\/40 (Refer to MIL-O-13830)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eFine-optically polished to ensure accurate 1\/4 wavefront and \u0026lt; 30 seconds parallelism over the both surfaces\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eHigh transmission at major nebula emission lines (i.e. H-alpha 656nm, OIII 496nm\u0026amp;500nm, SII 672nm and H-beta 486nm).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003ePrecision off-band blocking, specifically the major emission lines of artificial light pollution (i.e. Na 589nm, Hg 435nm and 578nm).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003e2. UBVRcIc Photometrics Spectrum and \u003c\/strong\u003e\u003cstrong\u003eCharacteristic\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0652\/6245\/2965\/files\/2b0bc9b7f5c81ec90e88024fd27b821c.webp?v=1778686732\" alt=\"\"\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eHow to read the chart?\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eThe horizontal axis is the Wavelength in Nanometers(nm).\u003c\/li\u003e\n\u003cli\u003eThe vertical axis is transmission in %\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003e3. Coating Technology\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e·Multi-layers anti-reflection coating\u003c\/p\u003e\n\u003cp\u003e·Non-cementing optical substrate coating\u003c\/p\u003e\n\u003cp\u003e·Optolong L-Pro filter adopts precision coating based on Ion-assisted deposition coating technology for durability and resistance to scratching, as well as stability on CWL(central wavelength) no deviation affected by temperature change.\u003c\/p\u003e\n\u003cp\u003e·Planetary rotation system offers precision and homogeneity of coatings ensuring high value on transmission of pass-band and Optical density of off-band.\u003c\/p\u003e\n\u003ch3\u003eIn the Box\u003c\/h3\u003e\n\u003cp\u003eOptolong Photometric UBVRcIc Filters\u003c\/p\u003e\n\u003ch3\u003e\n\u003cbr\u003e\u003cbr\u003eWarranty\u003c\/h3\u003e\n\u003cp\u003e\u003ca rel=\"noopener\" href=\"https:\/\/astronomyplus.com\/pages\/optolong-warranty\" target=\"_blank\"\u003eOptolong 3-year Warranty\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Optolong","offers":[{"title":"1.25\"","offer_id":49018980073701,"sku":"OPT-UBVRcIc-1.25","price":959.0,"currency_code":"CAD","in_stock":true},{"title":"2\"","offer_id":49018752991461,"sku":"OPT-UBVRcIc-2","price":1162.0,"currency_code":"CAD","in_stock":true},{"title":"36mm","offer_id":49018753024229,"sku":"OPT-UBVRcIc-36","price":1043.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0652\/6245\/2965\/files\/OptolongPhotometricUBVRcIcFilters_adf01a27-48ae-4a8f-a7db-29c44e69271b.webp?v=1778687138","url":"https:\/\/astronomyplus.com\/products\/optolong-photometric-ubvrcic-filters","provider":"Astronomy Plus – Telescopes \u0026 Astrophotography Canada","version":"1.0","type":"link"}