{"product_id":"altair-astro-2-dualband-3-5-nm-sii-oiii-with-test-report-copy","title":"Altair DualBand ULTRA 3.5nm Filter 2\" COMBO","description":"\u003ch2 data-section-id=\"1qov1nu\" data-start=\"0\" data-end=\"67\"\u003eAltair DualBand ULTRA 3.5nm Filter 2\" COMBO (Ha+OIII + SII+OIII)\u003c\/h2\u003e\n\u003cp data-start=\"69\" data-end=\"551\"\u003eThis combo is basically the cheat code for \u003cstrong data-start=\"112\" data-end=\"166\"\u003eSHO-style nebula imaging with a color (OSC) camera\u003c\/strong\u003e. You get \u003cstrong data-start=\"176\" data-end=\"215\"\u003etwo separate 3.5nm DualBand filters\u003c\/strong\u003e—one for \u003cstrong data-start=\"224\" data-end=\"235\"\u003eHa+OIII\u003c\/strong\u003e and one for \u003cstrong data-start=\"248\" data-end=\"260\"\u003eSII+OIII\u003c\/strong\u003e—so you can split \u003cstrong data-start=\"278\" data-end=\"315\"\u003eHa and SII into separate channels\u003c\/strong\u003e while also collecting \u003cstrong data-start=\"338\" data-end=\"361\"\u003etwice the OIII data\u003c\/strong\u003e (because OIII is present in both filters). The result: cleaner channel separation, more usable signal per night, and serious performance in bright moonlight or extreme city light pollution.\u003c\/p\u003e\n\u003cul data-start=\"553\" data-end=\"1912\"\u003e\n\u003cli data-section-id=\"ueoyw3\" data-start=\"553\" data-end=\"645\"\u003eBundle includes \u003cstrong data-start=\"571\" data-end=\"579\"\u003eboth\u003c\/strong\u003e DualBand ULTRA filters for a lower price than buying separately\u003c\/li\u003e\n\u003cli data-section-id=\"n10gz0\" data-start=\"646\" data-end=\"750\"\u003eDesigned for \u003cstrong data-start=\"661\" data-end=\"699\"\u003eOne Shot Colour (OSC) CMOS cameras\u003c\/strong\u003e (also useful with mono for luminance-style data)\u003c\/li\u003e\n\u003cli data-section-id=\"11fyj28\" data-start=\"751\" data-end=\"971\"\u003eEnables \u003cstrong data-start=\"761\" data-end=\"820\"\u003eproper SHO\/Hubble palette workflows with a color camera\u003c\/strong\u003e\n\u003cul data-start=\"825\" data-end=\"971\"\u003e\n\u003cli data-section-id=\"w3sfes\" data-start=\"825\" data-end=\"880\"\u003e\n\u003cstrong data-start=\"827\" data-end=\"855\"\u003eHa and SII are separated\u003c\/strong\u003e into different filters\u003c\/li\u003e\n\u003cli data-section-id=\"1t7ga01\" data-start=\"883\" data-end=\"971\"\u003e\n\u003cstrong data-start=\"885\" data-end=\"921\"\u003eOIII is captured in both filters\u003c\/strong\u003e, giving \u003cstrong data-start=\"930\" data-end=\"950\"\u003e2x the OIII data\u003c\/strong\u003e when used together\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"1jx34rt\" data-start=\"972\" data-end=\"1065\"\u003eBuilt for \u003cstrong data-start=\"984\" data-end=\"1032\"\u003ebright moonlight and extreme light pollution\u003c\/strong\u003e (major city center conditions)\u003c\/li\u003e\n\u003cli data-section-id=\"fduclj\" data-start=\"1066\" data-end=\"1165\"\u003e\n\u003cstrong data-start=\"1068\" data-end=\"1095\"\u003eUltra-narrow 3.5nm FWHM\u003c\/strong\u003e with steep bandpasses for maximum contrast and signal vs background\u003c\/li\u003e\n\u003cli data-section-id=\"fp6ucw\" data-start=\"1166\" data-end=\"1288\"\u003e\n\u003cstrong data-start=\"1168\" data-end=\"1184\"\u003eOD6 blocking\u003c\/strong\u003e (≈0.0001%) across most unwanted wavelengths for strong suppression of skyglow and artificial lighting\u003c\/li\u003e\n\u003cli data-section-id=\"h0ykhh\" data-start=\"1289\" data-end=\"1356\"\u003e\n\u003cstrong data-start=\"1291\" data-end=\"1311\"\u003eHalo suppression\u003c\/strong\u003e anti-reflective coatings for cleaner stars\u003c\/li\u003e\n\u003cli data-section-id=\"xpczmp\" data-start=\"1357\" data-end=\"1435\"\u003e\n\u003cstrong data-start=\"1359\" data-end=\"1386\"\u003eUV\/IR blocking included\u003c\/strong\u003e (works with modified and unmodified DSLRs too)\u003c\/li\u003e\n\u003cli data-section-id=\"1bkdz78\" data-start=\"1436\" data-end=\"1581\"\u003eStrong performance with fast optics\n\u003cul data-start=\"1478\" data-end=\"1581\"\u003e\n\u003cli data-section-id=\"1fevd54\" data-start=\"1478\" data-end=\"1581\"\u003eBest performance at focal ratios as fast as \u003cstrong data-start=\"1524\" data-end=\"1533\"\u003ef\/4.8\u003c\/strong\u003e, with contrast improving as focal ratio slows\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"1hw6zr3\" data-start=\"1582\" data-end=\"1742\"\u003eStandard \u003cstrong data-start=\"1593\" data-end=\"1608\"\u003e2\" M48x0.75\u003c\/strong\u003e thread\n\u003cul data-start=\"1620\" data-end=\"1742\"\u003e\n\u003cli data-section-id=\"z3u6xk\" data-start=\"1620\" data-end=\"1742\"\u003eFits standard 2\" filter wheels and holders (including Altair magnetic holders and common DSLR lens-to-camera adapters)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"54jxzl\" data-start=\"1743\" data-end=\"1912\"\u003e\n\u003cstrong data-start=\"1745\" data-end=\"1782\"\u003eIndividually tested and certified\u003c\/strong\u003e\n\u003cul data-start=\"1787\" data-end=\"1912\"\u003e\n\u003cli data-section-id=\"5bsahd\" data-start=\"1787\" data-end=\"1912\"\u003eEach filter includes its \u003cstrong data-start=\"1814\" data-end=\"1821\"\u003eown\u003c\/strong\u003e professional \u003cstrong data-start=\"1835\" data-end=\"1865\"\u003espectrographic test report\u003c\/strong\u003e (0.1nm resolution), not a generic batch report\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch1 data-section-id=\"1spgaq0\" data-start=\"1914\" data-end=\"1930\"\u003eSpecifications\u003c\/h1\u003e\n\u003cul data-start=\"1931\" data-end=\"2545\"\u003e\n\u003cli data-section-id=\"vrtt1m\" data-start=\"1931\" data-end=\"1978\"\u003e\n\u003cstrong data-start=\"1933\" data-end=\"1944\"\u003eFormat:\u003c\/strong\u003e 2\" mounted, \u003cstrong data-start=\"1957\" data-end=\"1969\"\u003eM48x0.75\u003c\/strong\u003e thread\u003c\/li\u003e\n\u003cli data-section-id=\"1vvcamo\" data-start=\"1979\" data-end=\"2087\"\u003e\n\u003cstrong data-start=\"1981\" data-end=\"1998\"\u003eSet contents:\u003c\/strong\u003e\n\u003cul data-start=\"2003\" data-end=\"2087\"\u003e\n\u003cli data-section-id=\"1o8zt4d\" data-start=\"2003\" data-end=\"2043\"\u003eDualBand \u003cstrong data-start=\"2014\" data-end=\"2027\"\u003eHa + OIII\u003c\/strong\u003e ULTRA (3.5nm)\u003c\/li\u003e\n\u003cli data-section-id=\"1an5sn\" data-start=\"2046\" data-end=\"2087\"\u003eDualBand \u003cstrong data-start=\"2057\" data-end=\"2071\"\u003eSII + OIII\u003c\/strong\u003e ULTRA (3.5nm)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"x3azlo\" data-start=\"2088\" data-end=\"2163\"\u003e\n\u003cstrong data-start=\"2090\" data-end=\"2109\"\u003eBandpass width:\u003c\/strong\u003e \u003cstrong data-start=\"2110\" data-end=\"2124\"\u003e3.5nm FWHM\u003c\/strong\u003e (steep bandpasses for high contrast)\u003c\/li\u003e\n\u003cli data-section-id=\"856i6g\" data-start=\"2164\" data-end=\"2242\"\u003e\n\u003cstrong data-start=\"2166\" data-end=\"2179\"\u003eBlocking:\u003c\/strong\u003e \u003cstrong data-start=\"2180\" data-end=\"2187\"\u003eOD6\u003c\/strong\u003e (≈0.0001%) over the majority of unwanted wavelengths\u003c\/li\u003e\n\u003cli data-section-id=\"10p6zct\" data-start=\"2243\" data-end=\"2320\"\u003e\n\u003cstrong data-start=\"2245\" data-end=\"2279\"\u003eGlass thickness \/ parfocality:\u003c\/strong\u003e \u003cstrong data-start=\"2280\" data-end=\"2290\"\u003e1.85mm\u003c\/strong\u003e optical glass, \u003cstrong data-start=\"2306\" data-end=\"2318\"\u003eparfocal\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"1jc1bt4\" data-start=\"2321\" data-end=\"2356\"\u003e\n\u003cstrong data-start=\"2323\" data-end=\"2339\"\u003eParallelism:\u003c\/strong\u003e \u003cstrong data-start=\"2340\" data-end=\"2354\"\u003e30 arc sec\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"1lur3l9\" data-start=\"2357\" data-end=\"2444\"\u003e\n\u003cstrong data-start=\"2359\" data-end=\"2372\"\u003eCoatings:\u003c\/strong\u003e SiO2 hard overcoat + UV\/IR block + anti-reflection \/ halo suppression\u003c\/li\u003e\n\u003cli data-section-id=\"14161tz\" data-start=\"2445\" data-end=\"2545\"\u003e\n\u003cstrong data-start=\"2447\" data-end=\"2476\"\u003eRecommended optics speed:\u003c\/strong\u003e Best down to \u003cstrong data-start=\"2490\" data-end=\"2499\"\u003ef\/4.8\u003c\/strong\u003e (contrast increases as focal ratio increases)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-start=\"2547\" data-end=\"2584\"\u003e\u003cstrong data-start=\"2547\" data-end=\"2584\"\u003eDualBand SII + OIII ULTRA (3.5nm)\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"2585\" data-end=\"2745\"\u003e\n\u003cli data-section-id=\"sg3xnu\" data-start=\"2585\" data-end=\"2666\"\u003e\n\u003cstrong data-start=\"2587\" data-end=\"2596\"\u003eOIII:\u003c\/strong\u003e CWL \u003cstrong data-start=\"2601\" data-end=\"2612\"\u003e500.7nm\u003c\/strong\u003e, FWHM tolerance ~\u003cstrong data-start=\"2630\" data-end=\"2639\"\u003e0.2nm\u003c\/strong\u003e, Transmission \u003cstrong data-start=\"2654\" data-end=\"2664\"\u003e90–95%\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"1c4zb4r\" data-start=\"2667\" data-end=\"2745\"\u003e\n\u003cstrong data-start=\"2669\" data-end=\"2677\"\u003eSII:\u003c\/strong\u003e CWL \u003cstrong data-start=\"2682\" data-end=\"2693\"\u003e671.6nm\u003c\/strong\u003e, FWHM tolerance ~\u003cstrong data-start=\"2711\" data-end=\"2720\"\u003e0.2nm\u003c\/strong\u003e, Transmission \u003cstrong data-start=\"2735\" data-end=\"2745\"\u003e90–95%\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-start=\"2747\" data-end=\"2783\"\u003e\u003cstrong data-start=\"2747\" data-end=\"2783\"\u003eDualBand Ha + OIII ULTRA (3.5nm)\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"2784\" data-end=\"2943\"\u003e\n\u003cli data-section-id=\"sg3xnu\" data-start=\"2784\" data-end=\"2865\"\u003e\n\u003cstrong data-start=\"2786\" data-end=\"2795\"\u003eOIII:\u003c\/strong\u003e CWL \u003cstrong data-start=\"2800\" data-end=\"2811\"\u003e500.7nm\u003c\/strong\u003e, FWHM tolerance ~\u003cstrong data-start=\"2829\" data-end=\"2838\"\u003e0.2nm\u003c\/strong\u003e, Transmission \u003cstrong data-start=\"2853\" data-end=\"2863\"\u003e90–95%\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"1mjfu69\" data-start=\"2866\" data-end=\"2943\"\u003e\n\u003cstrong data-start=\"2868\" data-end=\"2875\"\u003eHa:\u003c\/strong\u003e CWL \u003cstrong data-start=\"2880\" data-end=\"2891\"\u003e656.3nm\u003c\/strong\u003e, FWHM tolerance ~\u003cstrong data-start=\"2909\" data-end=\"2918\"\u003e0.2nm\u003c\/strong\u003e, Transmission \u003cstrong data-start=\"2933\" data-end=\"2943\"\u003e90–95%\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch1 data-section-id=\"1hj4hv6\" data-start=\"2945\" data-end=\"2965\"\u003eWhat’s in the box?\u003c\/h1\u003e\n\u003cul data-start=\"2966\" data-end=\"3201\"\u003e\n\u003cli data-section-id=\"jhenoc\" data-start=\"2966\" data-end=\"3014\"\u003e\u003cstrong data-start=\"2968\" data-end=\"3012\"\u003e3.5nm DualBand Ha + OIII ULTRA 2\" filter\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli data-section-id=\"1vtb2np\" data-start=\"3015\" data-end=\"3083\"\u003e\n\u003cstrong data-start=\"3017\" data-end=\"3058\"\u003eIndividual spectrographic test report\u003c\/strong\u003e for the Ha+OIII filter\u003c\/li\u003e\n\u003cli data-section-id=\"1nzaphi\" data-start=\"3084\" data-end=\"3133\"\u003e\u003cstrong data-start=\"3086\" data-end=\"3131\"\u003e3.5nm DualBand SII + OIII ULTRA 2\" filter\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli data-section-id=\"1pef5fz\" data-start=\"3134\" data-end=\"3201\"\u003e\n\u003cstrong data-start=\"3136\" data-end=\"3177\"\u003eIndividual spectrographic test report\u003c\/strong\u003e for the SII+OIII filter\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch1 data-section-id=\"lm8ipl\" data-start=\"3203\" data-end=\"3222\"\u003eSoftware and Docs\u003c\/h1\u003e\n\u003cul data-start=\"3223\" data-end=\"3442\" data-is-last-node=\"\" data-is-only-node=\"\"\u003e\n\u003cli data-section-id=\"sp1elp\" data-start=\"3223\" data-end=\"3292\"\u003eIndividual spectrographic test reports (included for each filter)\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Altair Astro","offers":[{"title":"Default Title","offer_id":52092654354752,"sku":"F200DB35NM-HSO-COMBO","price":974.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0717\/9904\/6464\/files\/altair-dualband-ultra-3.5nm-filter-2-combo-16009-p.jpg?v=1780700032","url":"https:\/\/astroworldtelescopes.com\/products\/altair-astro-2-dualband-3-5-nm-sii-oiii-with-test-report-copy","provider":"Astroworld Telescopes","version":"1.0","type":"link"}