{"product_id":"optolong-hydrogen-alpha-narrowband-3nm","title":"Optolong Hydrogen Alpha Narrowband 3nm","description":"\u003ch1\u003eOptolong Hydrogen Alpha Narrowband 3nm\u003c\/h1\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cdiv class=\"prose\"\u003e\n\u003cp\u003eOriginal manufacturer description below. Improved description\/specifications coming soon.\u003c\/p\u003e\n\u003cp\u003eH-Alpha 3nm filter is the popular narrowband filter allowing 3nm bandwidth of light centered on a wavelength of 656nm through, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapor, and both high and low pressure vapor lights and unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow). Better choice of narrowband H-Alpha astrophotographer filter for highest contrast and revealing subtle nebula details.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eGive you higher contrast and greater detailed viewing\u003c\/li\u003e\n\u003cli\u003eDecrease background noise and improve the contrast of objects\u003c\/li\u003e\n\u003cli\u003eIncrease the faint nebula signal to make it brighter\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003ctable style=\"width: 100%; height: 529.2px;\"\u003e\n\u003cthead\u003e\n\u003ctr style=\"height: 19.6px;\"\u003e\n\u003cth style=\"width: 27.2812%; height: 19.6px;\"\u003e\u003cstrong\u003eParameter\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth style=\"width: 69.9362%; height: 19.6px;\"\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr style=\"height: 19.6px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 19.6px;\"\u003e\u003cstrong\u003eModel \/ Part\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 19.6px;\"\u003eOptolong H-Alpha 3 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.6px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 19.6px;\"\u003e\u003cstrong\u003eType\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 19.6px;\"\u003eNarrowband (line) filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 39.2px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 39.2px;\"\u003e\u003cstrong\u003eCentral Wavelength (CWL)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 39.2px;\"\u003e 656 nm (H-alpha)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 39.2px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 39.2px;\"\u003e\u003cstrong\u003eFull Width at Half Maximum (FWHM)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 39.2px;\"\u003e3 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 39.2px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 39.2px;\"\u003e\u003cstrong\u003eTransmission (Peak)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 39.2px;\"\u003eHigh transmission\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.6px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 19.6px;\"\u003e\u003cstrong\u003eBlocking Range\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 19.6px;\"\u003e~ 300–1000 nm (for related dual-band versions)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 39.2px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 39.2px;\"\u003e\u003cstrong\u003eBlocking Depth \/ Optical Density\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 39.2px;\"\u003e\u0026gt; OD4 (in related L-Ultimate filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.6px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 19.6px;\"\u003e\u003cstrong\u003eSubstrate Material\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 19.6px;\"\u003eOptical glass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.6px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 19.6px;\"\u003e\u003cstrong\u003eGlass Thickness\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 19.6px;\"\u003e2″ version: ~1.85 mm; 36 mm unmounted: ~2.0 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.6px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 19.6px;\"\u003e\u003cstrong\u003eSurface Quality\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 19.6px;\"\u003e60\/40 (MIL-O-13830)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 39.2px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 39.2px;\"\u003e\u003cstrong\u003eTransmitted Wavefront Error\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 39.2px;\"\u003e~λ\/4 (manufacturer polishing)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.6px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 19.6px;\"\u003e\u003cstrong\u003eParallelism\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 19.6px;\"\u003e\u0026lt; 30 arc-seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 58.8px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 58.8px;\"\u003e\u003cstrong\u003eCoating Technology\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 58.8px;\"\u003eIon-assisted deposition, multi-layer anti-reflection; non-cemented substrate; homogeneous coating via planetary rotation system\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 39.2px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 39.2px;\"\u003e\u003cstrong\u003eFilter Cell \/ Mount\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 39.2px;\"\u003eFor 2″ version: ultra-thin CNC-machined metal cell; for 36 mm version: unmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.6px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 19.6px;\"\u003e\u003cstrong\u003eClear Aperture\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 19.6px;\"\u003e~45 mm for the 2″ version\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 39.2px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 39.2px;\"\u003e\u003cstrong\u003eUse Case \/ Application\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 39.2px;\"\u003eDeep-sky narrowband imaging (e.g., H-II regions, emission nebulae)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.6px;\"\u003e\n\u003ctd style=\"width: 27.2812%; height: 19.6px;\"\u003e\u003cstrong\u003eLimitations \/ Warnings\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"width: 69.9362%; height: 19.6px;\"\u003eNot designed for solar observation — do \u003cem\u003enot\u003c\/em\u003e use to view the Sun.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch3\u003eIn the Box\u003c\/h3\u003e\n\u003cp\u003e- Optolong Hydrogen Alpha Narrowband 3nm\u003c\/p\u003e\n\u003ch3\u003e\n\u003cbr\u003e\u003cbr\u003eWarranty\u003c\/h3\u003e\n\u003cp\u003e\u003ca rel=\"noopener\" href=\"https:\/\/istronomyplus.com\/pages\/optolong-warranty\" target=\"_blank\"\u003eOptolong 3-year Warranty\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Optolong","offers":[{"title":"2\"","offer_id":48076724830437,"sku":"OPT-HA3-2","price":587.0,"currency_code":"CAD","in_stock":true},{"title":"36mm","offer_id":48076724863205,"sku":"OPT-HA3-36","price":475.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0652\/6245\/2965\/files\/ofil-ol-ha7-2in.webp?v=1763842639","url":"https:\/\/istronomyplus.com\/products\/optolong-hydrogen-alpha-narrowband-3nm","provider":"Astronomy Plus – Telescopes \u0026 Astrophotography Canada","version":"1.0","type":"link"}