{"product_id":"zwo-duo-band-filter-1-25","title":"ZWO Duo-Band Dual-Bandpass Narrowband Imaging Filter - 1.25\"","description":"\u003cp\u003eThe ZWO Duo-Band Filter is a dual narrowband imaging filter designed for one-shot colour (OSC) astronomy cameras. By isolating the important H-alpha (656.3nm) and OIII (500nm) emission lines, it enhances contrast in nebulae while reducing the effects of moonlight and urban light pollution.\u003c\/p\u003e\n\n\u003cp\u003eIdeal for deep-sky astrophotography, the Duo-Band filter allows colour camera users to capture narrowband-style images without the need for a monochrome camera, filter wheel and multiple filters.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eKey Features\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n\u003cli\u003eDual-bandpass design for H-alpha and OIII emission lines\u003c\/li\u003e\n\u003cli\u003eImproves contrast on emission nebulae\u003c\/li\u003e\n\u003cli\u003eReduces light pollution and moonlight interference\u003c\/li\u003e\n\u003cli\u003eExcellent choice for one-shot colour cameras\u003c\/li\u003e\n\u003cli\u003eCompatible with ZWO ASI cameras and EFW filter wheels\u003c\/li\u003e\n\u003cli\u003ePrecision optical coatings for high transmission and minimal reflections\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0523\/1650\/4241\/files\/ZWO-Duo-Band-Filter-dual-narrowband-filter-1-1000x1000w.webp?v=1782214793\" alt=\"ZWO Duo-Band Filter\"\u003e\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eTechnical Specifications\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n\u003cli\u003eAvailable Sizes: 1.25\" and 2\"\u003c\/li\u003e\n\u003cli\u003eFilter Thickness: 1.85mm\u003c\/li\u003e\n\u003cli\u003eH-alpha Bandwidth: 15nm\u003c\/li\u003e\n\u003cli\u003eOIII Bandwidth: 35nm\u003c\/li\u003e\n\u003cli\u003eSchott optical glass substrate\u003c\/li\u003e\n\u003cli\u003e\u0026gt;90% transmission at OIII wavelengths\u003c\/li\u003e\n\u003cli\u003e\u0026gt;80% transmission at H-alpha wavelength\u003c\/li\u003e\n\u003cli\u003eSurface Quality: 60\/40 (MIL-O-13830)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0523\/1650\/4241\/files\/ZWO-Duo-Band-Filter-dual-narrowband-filter-1.25-inch-1000x1000w.webp?v=1782214794\" alt=\"ZWO Duo-Band Filter 1.25\"\u003e\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003ePrecision Construction\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n\u003cli\u003eCNC-machined aerometal housing\u003c\/li\u003e\n\u003cli\u003eFine sandblasted and anodised finish\u003c\/li\u003e\n\u003cli\u003eAnti-reflection extinction treatment\u003c\/li\u003e\n\u003cli\u003eLaser engraved markings\u003c\/li\u003e\n\u003cli\u003eDouble-sided precision optical coatings\u003c\/li\u003e\n\u003cli\u003eOptically polished for excellent wavefront accuracy\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0523\/1650\/4241\/files\/ZWO-Duo-Band-Filter-dual-narrowband-filter-2.webp?v=1782214794\" alt=\"Filter Transmission Diagram\"\u003e\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eImportant Note\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eFor optimum performance, incoming light should strike the filter as close to perpendicular as possible. This filter is not recommended for use with wide-angle or ultra-wide-angle camera lenses.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eReal-World Results\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThe examples below demonstrate the improvement in nebula contrast and detail when using the ZWO Duo-Band Filter in light-polluted conditions.\u003c\/p\u003e\n\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0523\/1650\/4241\/files\/ZWO-Duo-Band-Filter-dual-narrowband-filter-10.webp?v=1782214795\" alt=\"Duo-Band Filter Example\"\u003e\u003c\/p\u003e\n\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0523\/1650\/4241\/files\/ZWO-Duo-Band-Filter-dual-narrowband-filter-30.webp?v=1782214795\" alt=\"Duo-Band Filter Imaging Example\"\u003e\u003c\/p\u003e\n\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0523\/1650\/4241\/files\/ZWO-Duo-Band-Filter-dual-narrowband-filter-20.webp?v=1782214794\" alt=\"Duo-Band Filter Comparison\"\u003e\u003c\/p\u003e\n","brand":"ZWO","offers":[{"title":"Default Title","offer_id":55587436134776,"sku":"Z212-DB1.25","price":86.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0523\/1650\/4241\/files\/ZWO-Duo-Band-Filter-dual-narrowband-filter-1.25-inch-1000x1000w.webp?v=1782214794","url":"https:\/\/www.darkclearskies.co.uk\/products\/zwo-duo-band-filter-1-25","provider":"Dark Clear Skies ","version":"1.0","type":"link"}