{"product_id":"antlia-3nm-h-alpha-pro-series-filter-31-mm-ha-pro-3nm-31","title":"Antlia 3nm H-Alpha Pro Series Filter - 31 mm - HA-PRO-3NM-31","description":"\u003cp\u003eThis very narrowband 3 nm H-alpha filter from Antlia is part of their Pro series and is of the 31 mm unmounted variety.  It is normally used in a 1.25\"\/31mm filter wheel, where it drops into place.\u003c\/p\u003e\n\u003cp\u003e\u003cem\u003eImportant! Not for use when viewing or imaging the Sun!  \u003c\/em\u003e\u003c\/p\u003e\n\u003ch3 style=\"text-align: center;\"\u003eAntlia 3nm Pro Series H-Alpha Filter - 31 mm Unmounted\u003c\/h3\u003e\n\u003cp\u003e\u003cspan\u003eThis Antlia H-alpha Pro narrowband filter optimizes the FWHM (full width half maximum) to a 3nm\u003c\/span\u003e\u003cspan\u003e bandpass\u003c\/span\u003e\u003cspan\u003e. \u003c\/span\u003e\u003cspan\u003eAs the bandwidth becomes narrower, the 3nm Pro narrowband filters enhance contrast of emission targets by lowering the unwanted background signal. Antlia \u003c\/span\u003e\u003cspan\u003eH-alpha\u003c\/span\u003e\u003cspan\u003e 3nm Pro filter\u003c\/span\u003e\u003cspan\u003es\u003c\/span\u003e\u003cspan\u003e \u003c\/span\u003e\u003cspan\u003eare\u003c\/span\u003e\u003cspan\u003e designed to deliver 88\u003c\/span\u003e\u003cspan\u003e% transmission at the 656.3nm line which provides you with the maximum signal and well defined nebulae structures.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eConventional broader narrowband filters cause a heavy loss in transmission due to the strong Center Wavelength (CWL)-shift. Antlia guarantee T\u0026gt;88% within 1nm range of the center bandwidth,\u003c\/span\u003e\u003cspan\u003e \u003c\/span\u003e\u003cspan\u003ewhich means that the 3nm Pro narrowband filter can guarantee high transmittance for working with both long focal ratios and fast optical systems. \u003c\/span\u003e\u003cspan\u003eB\u003c\/span\u003e\u003cspan\u003elue\u003c\/span\u003e\u003cspan\u003e-\u003c\/span\u003e\u003cspan\u003eshift data shows that Antlia 3nm Pro filters can be used with nearly all systems as fast as f\/3 with minimal loss in emission signal\u003c\/span\u003e\u003cspan\u003e \u003c\/span\u003e\u003cspan\u003eand meets the requirements of fast optics like Hyperstar and RASA.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe out of band blocking specification is rated OD\u003c\/span\u003e\u003cspan\u003e5\u003c\/span\u003e\u003cspan\u003e (0.\u003c\/span\u003e\u003cspan\u003e00\u003c\/span\u003e\u003cspan\u003e1%) which delivers an excellent \u003c\/span\u003e\u003cspan\u003eSNR(\u003c\/span\u003e\u003cspan\u003esignal to noise ratio\u003c\/span\u003e\u003cspan\u003e)\u003c\/span\u003e\u003cspan\u003e and effective cut-off rate to minimize interference from other wavelengths.\u003c\/span\u003e\u003cspan\u003e \u003c\/span\u003e\u003cspan\u003eImproved \u003c\/span\u003e\u003cspan\u003es\u003c\/span\u003e\u003cspan\u003eharp cut-off astrophotography 3nm Pro filters are designed to minimize halos around bright stars.\u003c\/span\u003e\u003cspan\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cspan\u003eApplication and Performance:\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cspan\u003eHigh transmittance and smallest bandwidth \u003c\/span\u003e\u003cspan\u003eto maximize \u003c\/span\u003e\u003cspan\u003econtrast\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eSteep spectral profile minimizes halos around bright stars\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eA single substrate to eliminate internal reflections   \u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eNarrowband Objects: H-alpha Emission Nebulae, Planetary, Wolf Rayet Nebulae and Supernova Remnants\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eUse in light polluted areas and\u003c\/span\u003e\u003cspan\u003e \u003c\/span\u003e\u003cspan\u003edark sites\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eExtend\u003c\/span\u003e\u003cspan\u003es\u003c\/span\u003e\u003cspan\u003e imaging time when the moon is up\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eAntlia narrowband Pro filters can be used \u003c\/span\u003e\u003cspan\u003edown \u003c\/span\u003e\u003cspan\u003eto F\/3\u003c\/span\u003e\u003cspan\u003e systems\u003c\/span\u003e\u003cspan\u003e with slight loss of signal\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eAll A\u003c\/span\u003e\u003cspan\u003entlia\u003c\/span\u003e\u003cspan\u003e Narrowband filters are edge blackened to \u003c\/span\u003e\u003cspan\u003eeliminate internal reflections\u003c\/span\u003e\u003cspan\u003e from stray light\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eSuperior optical reliability reduces \u003c\/span\u003e\u003cspan\u003epost image processing\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThis filter is not suited to deep sky objects that do not contain \u003c\/span\u003e\u003cspan\u003eH-alpha\u003c\/span\u003e\u003cspan\u003e emissions.\u003c\/span\u003e\u003cspan\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3\u003e\n\u003cspan\u003eTechnical Specifications\u003c\/span\u003e\u003cspan\u003e:\u003c\/span\u003e\n\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eBasic Substrate:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Schott optical substrate\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eFilter Thickness:   \u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e2mm+\/-0.05mm\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eFWHM (Full width at half maximum): \u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e3nm\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eCWL (Central Wavelength)\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e: \u003c\/span\u003e\u003cspan\u003e656.3nm\u003c\/span\u003e\u003cspan\u003enm\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003ePeak Transmission:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e ＞88%\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eBlocking: \u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e\u0026gt; 5 OD(0.001%\u003c\/span\u003e\u003cspan\u003e out of band blocking\u003c\/span\u003e\u003cspan\u003e) @ 300-1000nm\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eSurface Quality: \u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003eS\/D (scratch\/dig)= 60\/40 (Refer to MIL-O-13830)\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eTransmitted Wavefront: \u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003eLambda\/4 or better.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan\u003eParallelism: \u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003eless than 30 arcsec\u003c\/span\u003e\u003c\/p\u003e","brand":"Antlia","offers":[{"title":"Default Title","offer_id":43012562255985,"sku":"ATL-HA-PRO-3NM-31","price":391.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/files\/HA_Pro_31mm_Filter.jpg?v=1776459060","url":"https:\/\/khanscope.com\/products\/antlia-3nm-h-alpha-pro-series-filter-31-mm-ha-pro-3nm-31","provider":"Khan Scope Centre","version":"1.0","type":"link"}