{"product_id":"antlia-alp-t-sii-hb-3-5nm-duo-band-2-filter","title":"Antlia ALP-T Dual Band SII \u0026 Hb 3.5nm 2\" Filter","description":"\u003ch1\u003eAntlia ALP-T Dual band 3.5nm SII\u0026amp;Hb 2'' Filter\u003c\/h1\u003e\n\u003ch4\u003eProduct Details\u003c\/h4\u003e\n\u003cdiv class=\"value\"\u003e\n\u003cdiv class=\"product attribute description\"\u003e\n\u003cdiv class=\"value\"\u003e\n\u003cdiv data-content-type=\"row\" data-appearance=\"contained\" data-element=\"main\"\u003e\n\u003cdiv data-enable-parallax=\"0\" data-parallax-speed=\"0.5\" data-background-images=\"{}\" data-background-type=\"image\" data-video-loop=\"true\" data-video-play-only-visible=\"true\" data-video-lazy-load=\"true\" data-video-fallback-src=\"\" data-element=\"inner\" data-pb-style=\"IISSWKQ\"\u003e\n\u003cdiv data-content-type=\"text\" data-appearance=\"default\" data-element=\"main\"\u003e\n\u003cp\u003eThe ALP-T dual band 3.5nm SII\u0026amp;Hb filter is a dual narrowband filter, which lets the deep red Sulfur-II 672.4nm and the blue Hydrogen-Beta 486.1nm lines through and is primarily engineered for color cameras to assist astrophotographers taking deep sky images with superior SNR (Signal to Noise Ratio). With an FWHM half-bandwidth designed at 3.5nm and achieving an optical density (OD) of 4.5 on unwanted wavelengths, it works strongly in blocking light pollution, moonlight, and airglow, leading to enhanced contrast in nebulae images by effectively passing the SII and H-beta emission lines signal only.\u003c\/p\u003e\n\u003cp\u003eIt is a significant addition to the popular Antlia ALP-T dual-band Ha\u0026amp;OIII filter and enables false-color images and narrow-band nebula images using OSC. When capturing data with this filter, the nebulae are recorded with high signal-to-noise ratios and greater contrast than without it.\u003c\/p\u003e\n\u003cp\u003eThe combination of these two dual band Ha\u0026amp;OIII and SII\u0026amp;H-beta filters allows extreme narrow-band images with OSC cameras by capturing the spectral data from 4 channels i.e. Ha\/OIII\/SII\/Hb. The spectrum of these four channels can be separated and recombined into various color palettes in your post-processing. The resulting images can be used for luminance contrast enhancement of traditional RGB-balanced images or the creation of images in various popular false-color palettes such as H-O-Hb, S-H-O, H-S-OHb, H-O-O, etc.\u003c\/p\u003e\n\u003cp\u003eThe advanced multi-coatings on Antlia ALP-T dual-band filters effectively isolate the red, Ha line, blue-green, OIII line, deep red SII, and the blue H-beta lines from emission nebulae, with almost total suppression of optical density (OD)4.5 on unwanted wavelengths from light pollution, moonlight, and airglow. The result is that both the ALP-T dual band Ha\u0026amp;OIII version and SII\u0026amp;Hb version create a superior signal-to-noise ratio and better contrast in your OSC images whether used in urban or rural areas, making them excellent choices for astrophotographers aiming to capture high-quality and more detailed celestial images.\/p\u0026gt;\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eMain features and application:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003ePasses SII 672.4nm and H-Beta 486.1nm lines\u003c\/li\u003e\n\u003cli\u003eCapturing of the two main emission wavebands in the deep red and blue at the same time\u003c\/li\u003e\n\u003cli\u003eUltra FWHM 3.5nm design allows for increasing exposure time and capturing detailed nebulae signal\u003c\/li\u003e\n\u003cli\u003eDesigned to be used primarily with color cameras to capture cleaner data or used as Luminance filter mono cameras to save imaging time\u003c\/li\u003e\n\u003cli\u003eRecommended to be used with ALP-T Dual Band Ha\u0026amp;OIII filter to create images with better\u003c\/li\u003e\n\u003cli\u003eSNR( signal-to-noise) and better isolation between the 4 channels\u003c\/li\u003e\n\u003cli\u003eSuppression of optical density (OD)4.5 on unwanted wavelengths improves SNR( signal-to-noise)\u003c\/li\u003e\n\u003cli\u003eNear IR (NIR) is blocked up to 1100nm\u003c\/li\u003e\n\u003cli\u003eIdeal flat-top and moderate bandpass reducing spectrum downshifts\u003c\/li\u003e\n\u003cli\u003eRecommended to use the filter with optics f-ratios slower than f\/4 for best performance, for optics faster than f\/4, pre-shifted highspeed version is a better choice\u003c\/li\u003e\n\u003cli\u003eIon Gun Assisted Deposition of double-sided multi-layer coating technology on the double-sided polished substrate making it the most consistent and accurate light pollution suppression filter\u003c\/li\u003e\n\u003cli\u003eHalo suppression anti-reflective coating is used to minimize halo and internal reflections\u003c\/li\u003e\n\u003cli\u003eDesigned to suppress artificial lighting from Bortle scale 1 to Bortle scale 8\u003c\/li\u003e\n\u003cli\u003eBlackened edges of unmounted sizes to minimize internal reflections\u003c\/li\u003e\n\u003cli\u003eAntlia's ever-trusted coating technology makes filter durability very reliable\u003c\/li\u003e\n\u003cli\u003eWhile primarily designed for use with color cameras, the filter is also highly effective with monochrome cameras to save imaging time\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eTechnical Data:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eFWHM: 3.5nm +0.5\/-0.5nm\u003c\/li\u003e\n\u003cli\u003eCWL (Central Wavelength):\n\u003cul\u003e\n\u003cli\u003eSulfur-II: 672.4nm\u003c\/li\u003e\n\u003cli\u003eHydrogen-Beta: 486.1nm\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003ePeak Transmission:\n\u003cul\u003e\n\u003cli\u003eSulfur-II: 90%\u003c\/li\u003e\n\u003cli\u003eHydrogen-Beta: 85%\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eBlocking: ≥OD4.5 @ 300-1100nm\u003c\/li\u003e\n\u003cli\u003eFilter Thickness: 2mm+\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eBasic Substrate Optical, Single \/ Non-glued substrate\u003c\/li\u003e\n\u003cli\u003eSurface Quality S\/D (scratch\/dig)= 60\/40 (Refer to MIL-O-13830)\u003c\/li\u003e\n\u003cli\u003eTransmitted Wavefront Lambda\/4 or better. Parallelism less than 30 arcsec\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eFilter Ring:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e2’’ Mounted (M48*0.75 thread)\u003c\/li\u003e\n\u003cli\u003eUltra-thin filter cell to minimize vignetting by maximizing possible clear aperture\u003c\/li\u003e\n\u003cli\u003eBlack Anodized Finish\u003c\/li\u003e\n\u003cli\u003eLaser Engraving, No Fading\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eNot Recommended:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eSolar Observing and imaging\u003c\/li\u003e\n\u003cli\u003eNight visual observation\u003c\/li\u003e\n\u003cli\u003eDO NOT LOOK AT THE SUN WITH ANTLIA FILTERS. Serious eye damage will result if you fail to observe the warning.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch3\u003eTechnical Specifications\u003cstrong\u003e\u003c\/strong\u003e\n\u003c\/h3\u003e\n\u003cp align=\"left\" class=\"western\"\u003e\u003cspan style=\"font-family: Arial, sans-serif;\" data-mce-style=\"font-family: Arial, sans-serif;\"\u003e\u003cspan style=\"font-size: small;\" data-mce-style=\"font-size: small;\"\u003e\u003cspan lang=\"en-US\"\u003e\u003cb\u003eAntlia ALP-T dualband 3.5nm SII\u0026amp;H-beta Filter\u003c\/b\u003e\u003c\/span\u003e\u003c\/span\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003ctable cellspacing=\"0\" border=\"0\"\u003e\n\u003ccolgroup width=\"241\"\u003e\u003c\/colgroup\u003e \u003ccolgroup width=\"214\"\u003e\u003c\/colgroup\u003e \u003ccolgroup width=\"235\"\u003e\u003c\/colgroup\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"\"}'\u003e\u003cbr\u003e\u003c\/td\u003e\n\u003ctd align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"Sulfur-II\"}'\u003e\u003cb\u003e\u003cspan style=\"color: #4d4d4d; font-family: Arial;\" data-mce-style=\"color: #4d4d4d; font-family: Arial;\"\u003eSulfur-II\u003c\/span\u003e\u003c\/b\u003e\u003c\/td\u003e\n\u003ctd align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"Hydrogen-Beta\"}'\u003e\u003cb\u003e\u003cspan style=\"color: #4d4d4d; font-family: Arial;\" data-mce-style=\"color: #4d4d4d; font-family: Arial;\"\u003eHydrogen-Beta\u003c\/span\u003e\u003c\/b\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"FWHM\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eFWHM\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"3.5nm +0.5\\\/-0.5nm\"}'\u003e\u003cspan style=\"color: #000000; font-family: Arial;\" data-mce-style=\"color: #000000; font-family: Arial;\"\u003e3.5nm +0.5\/-0.5nm\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"3.5nm +0.5\\\/-0.5nm\"}'\u003e\u003cspan style=\"color: #000000; font-family: Arial;\" data-mce-style=\"color: #000000; font-family: Arial;\"\u003e3.5nm +0.5\/-0.5nm\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"CWL (Central Wavelength)\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eCWL (Central Wavelength)\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"672.4nm\"}'\u003e\u003cspan style=\"color: #000000; font-family: Arial;\" data-mce-style=\"color: #000000; font-family: Arial;\"\u003e672.4nm\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"486.1nm\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003e486.1nm\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"Peak Transmission\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003ePeak Transmission\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd align=\"center\" data-sheets-value='{ \"1\": 3, \"3\": 0}' data-sheets-numberformat='{ \"1\": 2, \"2\": \"0.00%\", \"3\": 1}' sdval=\"0.9\" sdnum=\"1033;0;0.00%\"\u003e\u003cspan style=\"color: #000000; font-family: Arial;\" data-mce-style=\"color: #000000; font-family: Arial;\"\u003e90.00%\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd align=\"center\" data-sheets-value='{ \"1\": 3, \"3\": 0}' data-sheets-numberformat='{ \"1\": 2, \"2\": \"0.00%\", \"3\": 1}' sdval=\"0.85\" sdnum=\"1033;0;0.00%\"\u003e\u003cspan style=\"color: #000000; font-family: Arial;\" data-mce-style=\"color: #000000; font-family: Arial;\"\u003e85.00%\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"Blocking\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eBlocking\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\" align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"≥OD4.5 @ 300-1100nm\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003e≥OD4.5 @ 300-1100nm\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"Filter Thickness\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eFilter Thickness\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\" align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"2mm+\\\/-0.05mm\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003e2mm+\/-0.05mm\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"Basic Substrate\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eBasic Substrate\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\" align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \" Optical, Single \\\/ Non-glued substrate\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003e Optical, Single \/ Non-glued substrate\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"Surface Quality\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eSurface Quality\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\" align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"S\\\/D (scratch\\\/dig)= 60\\\/40 (Refer to MIL-O-13830\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eS\/D (scratch\/dig)= 60\/40 (Refer to MIL-O-13830\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"Transmitted Wavefront\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eTransmitted Wavefront\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\" align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"Lambda\\\/4 or better.\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eLambda\/4 or better.\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"Parallelism\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eParallelism\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\" align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"less than 30 arcsec\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eless than 30 arcsec\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd height=\"21\" align=\"left\" data-sheets-value='{ \"1\": 2, \"2\": \"Filter Ring\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003eFilter Ring\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd colspan=\"2\" align=\"center\" data-sheets-value='{ \"1\": 2, \"2\": \"2’’ (M48*0.75)\"}'\u003e\u003cspan style=\"font-family: Arial;\" data-mce-style=\"font-family: Arial;\"\u003e2’’ (M48*0.75)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003eFilter Ring:\u003cbr\u003e2’’ (M48*0.75)\u003cbr\u003eUltra-thin filter cell to minimize vignetting by maximize possible clear aperture\u003cbr\u003eBlack Anodized Finish\u003cbr\u003eLaser Engraving No Fading\u003c\/p\u003e\n\u003ch3\u003eIn the Box\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eAntlia ALP-T Dualband 3nm Ha\u0026amp;OIII Filter 2''\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eWarranty \u0026amp; Manual\u003c\/h3\u003e\n\u003cp\u003e\u003cspan\u003eAntlia 3-Years Warranty against Delamination\u003c\/span\u003e\u003c\/p\u003e","brand":"Antlia","offers":[{"title":"Default Title","offer_id":46135584293093,"sku":"AF-ALP-T-2-SIIHb-3.5nm","price":511.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0652\/6245\/2965\/files\/alp-t-2-siihb-3.5nm-2.jpg?v=1777043454","url":"https:\/\/istronomyplus.com\/products\/antlia-alp-t-sii-hb-3-5nm-duo-band-2-filter","provider":"Astronomy Plus – Telescopes \u0026 Astrophotography Canada","version":"1.0","type":"link"}