{"product_id":"optolong-1-25-ir-pass-685-nm-planetary-imaging-filter","title":"Optolong 1.25\" IR Pass 685 nm Planetary Imaging Filter","description":"\u003cdiv style=\"padding:20px;border-left:4px solid #168b9b;background:#f3f8fa;\"\u003e\n\u003ch2\u003eExplore lunar and planetary detail in near-infrared\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eThe Optolong IR Pass 685 nm filter in a 1.25-inch mounted cell is designed for lunar and planetary imaging with an infrared-sensitive camera.\u003c\/strong\u003e It passes near-infrared light while suppressing shorter visible wavelengths, helping you capture an IR image or a luminance layer for an IR-RGB composite.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0523\/1650\/4241\/files\/279f586ba3950648a68a93363a97bf87.jpg?v=1794074207\" alt=\"Optolong IR Pass 685 nm filter in its threaded mounting cell\" width=\"1428\" height=\"1428\" loading=\"lazy\" style=\"display:block;max-width:100%;width:520px;height:auto;margin:12px auto;\"\u003e\u003c\/p\u003e\n\u003ch2\u003eWhy use an IR-pass filter?\u003c\/h2\u003e\n\u003cp\u003eLonger wavelengths can be less affected by atmospheric seeing. Optolong designed the IR685 for imaging detail on the Moon and planets, including use as the luminance component of an IR-LRGB workflow. The benefit depends on the target, seeing conditions and the camera's sensitivity in this wavelength range.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLunar and planetary imaging:\u003c\/strong\u003e capture near-infrared detail on bright Solar System targets.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIR-RGB workflow:\u003c\/strong\u003e combine a separately captured IR image with RGB data when that approach suits your processing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.25-inch mounted format:\u003c\/strong\u003e supplied in a filter cell for compatible 1.25-inch filter holders.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProtective storage:\u003c\/strong\u003e supplied with a protective plastic case and EVA lining.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWhat does 685 nm mean?\u003c\/h2\u003e\n\u003cp\u003e685 nm identifies the filter's nominal transition region. This is a long-pass imaging filter, rather than a narrowband filter with a 685 nm bandwidth. Optolong describes it as suppressing wavelengths below approximately 670 nm, with transmission rising into the near-infrared.\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0523\/1650\/4241\/files\/f38d04404d461d5c64dd2159dc025330.png?v=1794074208\" alt=\"Optolong IR Pass 685 nm reference transmission curve showing rising transmission into the near-infrared\" width=\"631\" height=\"346\" loading=\"lazy\" style=\"display:block;max-width:100%;height:auto;margin:20px auto;\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003csmall\u003eManufacturer reference transmission curve, provided as a guide rather than an individual test certificate.\u003c\/small\u003e\u003c\/p\u003e\n\u003ch2\u003eCamera and filter-holder compatibility\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eYour camera and optical path must transmit near-infrared light.\u003c\/strong\u003e Check the camera's spectral response and sensor-window specification. A UV\/IR-cut filter or IR-blocking camera window will suppress the light this filter is intended to pass.\u003c\/p\u003e\n\u003cp\u003eCheck that your filter wheel, drawer or camera nosepiece accepts mounted 1.25-inch filters and has sufficient clearance. Refocus after fitting the filter and take a short test sequence before committing to a longer capture.\u003c\/p\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eBrand\u003c\/th\u003e\n\u003ctd\u003eOptolong\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eModel\u003c\/th\u003e\n\u003ctd\u003eIR Pass 685 nm \/ IR685\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eSupplied size\u003c\/th\u003e\n\u003ctd\u003e1.25-inch mounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eFilter type\u003c\/th\u003e\n\u003ctd\u003eNear-infrared long-pass imaging filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eNominal transition designation\u003c\/th\u003e\n\u003ctd\u003e685 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eMain applications\u003c\/th\u003e\n\u003ctd\u003eLunar and planetary imaging; IR-LRGB luminance capture\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eCamera requirement\u003c\/th\u003e\n\u003ctd\u003eNear-infrared sensitivity with a suitable optical path\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch2\u003eWhat's included\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eOne Optolong IR Pass 685 nm filter in a 1.25-inch mounting cell.\u003c\/li\u003e\n\u003cli\u003eProtective plastic case with EVA lining.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eFor imaging. Not a solar filter.\u003c\/strong\u003e Do not use this filter to observe or photograph the Sun.\u003c\/p\u003e\n\u003cp\u003eBrowse the \u003ca href=\"https:\/\/www.darkclearskies.co.uk\/collections\/optolong\"\u003eOptolong filter range at Dark Clear Skies\u003c\/a\u003e or consult \u003ca href=\"https:\/\/www.optolong.com\/cms\/document\/detail\/id\/102.html\"\u003eOptolong's IR Pass 685 product information\u003c\/a\u003e.\u003c\/p\u003e","brand":"Optolong","offers":[{"title":"1.25\"","offer_id":55729648173432,"sku":"OPT-IR685-125","price":59.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0523\/1650\/4241\/files\/279f586ba3950648a68a93363a97bf87.jpg?v=1794074207","url":"https:\/\/www.darkclearskies.co.uk\/products\/optolong-1-25-ir-pass-685-nm-planetary-imaging-filter","provider":"Dark Clear Skies ","version":"1.0","type":"link"}