{"product_id":"optolong-l-extreme-dual-band-narrow-band-filter-l-extreme","title":"Optolong L-Extreme Dual-Band Filter","description":"\u003ch1\u003eOptolong L-Extreme Dual-Band Astronomy NarrowBand Filter\u003c\/h1\u003e\n\u003cp\u003eThe advantage of the L-eXtreme filter is that there is no transmission between the H-beta and OIII lines and there are also no nebula emission lines there. In this case, it isn’t letting light pollution come through so it maximizes nebula signals and the sky background is made darker while imaging.\u003c\/p\u003e\n\u003cp\u003eThe L-eXtreme filter should better isolate the emission lines and better protect from light pollution.\u003c\/p\u003e\n\u003ch4\u003eL-Extreme Introduction\u003c\/h4\u003e\n\u003cp\u003eOptolong L-eXtreme is a two 7 nm bandpass filter which can be used with one-shot color cameras like DSLR’s (digital SLR), and monochrome CCD cameras, it is also more suited for fast systems. The convenience and cost-effectiveness of this filter allows amateurs to image a rich emission nebula, even in bright, light pollution skies. Optolong believes the design of L-eXtreme filter would be a better choice for fast systems at a competitive price. It isolates the H-alpha, and Oxygen-iii nebula emission lines so that the contrast and signal-to-noise ratio between nebulae were maximized. For people who are living in very light-polluted areas, or when the moon is out, the L-eXtreme will be a good filter.\u003c\/p\u003e\n\u003cp\u003eUnlike the L-eNhance filter which is a tri-band (transmits H-b, H-a, and O-iii), the L-eXtreme filter is dual-band that passes H-a and O-iii emission lines.\u003c\/p\u003e\n\u003cp\u003eHydrogen is the largest, the most primitive, the simplest, and the oldest element in the universe. Scientists consider that Hydrogen amounts to more than 90% of visible substance in space. Our sun is 5 billion years old, but so far hydrogen is still the key matter of nuclear fusion. While the sulfur element does not have much scientific significance, so keeping H and O for the exploration of life.\u003c\/p\u003e\n\u003cp\u003eTherefore, Optolong highlights H-a, H-b, O-iii, and O-ii, and reduce the signal of sulfur.\u003c\/p\u003e\n\u003ch4\u003eL-eXtreme Performance:\u003c\/h4\u003e\n\u003cp\u003e\u003cu\u003e\u003cstrong\u003eI. Compare: L-eXtreme VS no filter © Vincent Cheng\u003c\/strong\u003e\u003c\/u\u003e \u003cimg height=\"489\" width=\"457\" alt=\"\" src=\"http:\/\/www.optolong.com\/uploads\/images\/20200716\/5bcdb1e79c79231df851f9b60f152ba9.png\" class=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cu\u003e\u003cstrong\u003eII. NGC6946, Barnard 150 \u0026amp; Sh2-129 Flying Bat nebula ©José Jiménez\u003c\/strong\u003e\u003c\/u\u003e NGC6946, Barnard 150 \u0026amp; Sh2-129 Flying Bat nebula Canon 6D mod \u0026amp; WO SpaceCat 51 RGB 25 x 600\" ISO 3200 - Optolong L-Pro H-Alpha \u0026amp; OIII 20 x 1500\" ISO 3200 -\u003cu\u003e \u003cstrong\u003eOptolong L-eXtreme\u003c\/strong\u003e\u003c\/u\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg height=\"252\" width=\"503\" alt=\"\" src=\"http:\/\/www.optolong.com\/uploads\/images\/20200716\/1840a8e24b716e2297a92bd4aa933ede.jpg\" class=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cu\u003e\u003cstrong\u003eIII. The Rosette and Cone Nebulas ©Starizona\u003c\/strong\u003e\u003c\/u\u003e The image of the Rosette and Cone Nebulas is an example under about the worst conditions: a very wide field of view (135mm lens, 8 x 5.5 degrees), a very fast focal ratio (f\/1.8) and with the 58% illuminated moon only 17 degrees outside the field of view!  It is 20 exposures of 90 seconds each with the ZWO ASI294.\u003c\/p\u003e\n\u003cp\u003e\u003cimg height=\"343\" width=\"500\" alt=\"\" src=\"http:\/\/www.optolong.com\/uploads\/images\/20200716\/5d3cbec016b1e67e43be0157c53c10a8.jpg\" class=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cu\u003e\u003cstrong\u003eIV. IC1396 Elephant Trunk nebula ©José Jiménez \u003c\/strong\u003e\u003c\/u\u003e A new job with Optolong L-eXtreme filter and the new Askar Lens FRA 400 tube; IC1396 Elephant Trunk nebula La Jonquera - Girona - Spain May 2020 Equipment used : Canon 6D mod Askar FRA 400mm Sharpstar Optics Fong Michael RGB 6 x 1500\" ISO 6400 \u003cu\u003e\u003cstrong\u003eOptolong L-eXtreme\u003c\/strong\u003e\u003c\/u\u003e Sky Watcher EQ6 Mount Guide camera QHY5 Flats, Darks \u0026amp; Bias Calibrated, stacked and processed with Pixinsight, final tweaks with Lightroom\u003c\/p\u003e\n\u003cp\u003e\u003cimg height=\"331\" width=\"504\" alt=\"\" src=\"http:\/\/www.optolong.com\/uploads\/images\/20200716\/fd6ecb8b50249153970ab1b4eb64223e.jpg\" class=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cu\u003e\u003cstrong\u003eV. NGC6188 Fighting Dragons of Ara  ©Tommy Lim KW  \u003c\/strong\u003e\u003c\/u\u003e OBJECTS: NGC6188 FIGHTING DRAGONS OF ARA LOCATION: MERSING, JOHOR CAMERA: QHY168C TELESCOPE: 4\" REFRACTOR MOUNT: SKYWATCHER AZ-EQ5GT FILTERS: OPTOLONG L-EXTREME FILTER. EXPOSURE: 30 X 300SEC Stacked in Siril and processed in Pixinsight.\u003c\/p\u003e\n\u003cp\u003e\u003cimg height=\"327\" width=\"508\" alt=\"\" src=\"http:\/\/www.optolong.com\/uploads\/images\/20200716\/e2b193114d02ba2a75138093d52f0e1c.jpg\" class=\"\"\u003e \u003cstrong\u003eWarm prompt\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eAbout color: due to the influence of ambient light, color difference of the display and flash photography, the color of the product may have some color difference. Detailed color is in accordana with the final product.\u003c\/li\u003e\n\u003cli\u003eAbout coating: the interference filter will show different colors under different light, which is a normal phenomenon. Please refer to the material object.\u003c\/li\u003e\n\u003cli\u003eAbout the style: in order to improve the product, the change of design\/appearance\/parameters has not been updated in time. Please see the subject produce.\u003c\/li\u003e\n\u003cli\u003eAbout the description: the series of this product have the same material, technology and design, different sizes only, please note.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003ch4\u003eSpectrum and Characteristic:\u003c\/h4\u003e\n\u003cp\u003e\u003cspan\u003eSbustrate: B270\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eThickness: 1.85mm\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eTpeak:  T\u0026gt;90%\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eBlocking range: 300-1000nm\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eBlocking depth: light pollution  line blocking \u0026gt;99%\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eSurface quality: 60\/40\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eTransmitted Wavefront RMS: λ\/4\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eParallelism: 30s\u003c\/span\u003e\u003c\/p\u003e\n\u003cp data-mce-fragment=\"1\"\u003e\u003cstrong data-mce-fragment=\"1\"\u003eHow to read the chart?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-mce-fragment=\"1\"\u003e▲The horizontal axis is the Wavelength in Nanometers(nm).\u003c\/p\u003e\n\u003cp data-mce-fragment=\"1\"\u003e▲The vertical axis is transmission in %.\u003c\/p\u003e\n\u003cp data-mce-fragment=\"1\"\u003e▲The \u003cspan style=\"color: #bc1f1f;\"\u003e\u003cstrong data-mce-fragment=\"1\"\u003eRED\u003c\/strong\u003e\u003c\/span\u003e line shows the line of H-alpha.\u003cspan data-mce-fragment=\"1\"\u003e \u003c\/span\u003e\u003cspan data-mce-fragment=\"1\" style=\"color: #038b0b;\"\u003e\u003cstrong data-mce-fragment=\"1\"\u003eGREEN\u003c\/strong\u003e\u003c\/span\u003e\u003cspan data-mce-fragment=\"1\"\u003e \u003c\/span\u003eline shows the emmission of OIII. The artifical emission lines are shown in \u003cspan data-mce-fragment=\"1\"\u003e\u003cspan style=\"color: #ff8000;\"\u003e\u003cstrong data-mce-fragment=\"1\"\u003eORANGE\u003c\/strong\u003e\u003c\/span\u003e.\u003c\/span\u003e\u003cimg height=\"110\" width=\"668\" data-mce-fragment=\"1\" data-ll-status=\"loaded\" alt=\"\" src=\"http:\/\/www.optolong.com\/uploads\/images\/20191111\/0ff2d7f395c427aa390ff53daf333cec.jpg\" class=\"aligncenter lazyloaded\"\u003e\u003c\/p\u003e\n\u003ch4\u003eCoating Technology\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eMulti-layers anti-reflection coating\u003c\/li\u003e\n\u003cli\u003eNon-cementing optical substrate coating\u003c\/li\u003e\n\u003cli\u003eOptolong filter adopts precision coating based on Ion-assisted deposition coating technology for durability and resistance to scratching, as well as stability on CWL (central wavelength) no deviation affected by temperature change.\u003c\/li\u003e\n\u003cli\u003ePlanetary rotation system offers precision and homogeneity of coatings ensuring high value on transmission of pass-band and Optical density of off-band.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003ePacking\u003c\/em\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eOuter Box: silve box\u003c\/li\u003e\n\u003cli\u003ePlastic Box: PP material\u003c\/li\u003e\n\u003cli\u003eLining: imported high pressure white EVA material\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cbr\u003e\u003c\/h3\u003e\n\u003cul\u003e\u003c\/ul\u003e","brand":"Optolong","offers":[{"title":"1.25\"","offer_id":43697369940197,"sku":"OL-L-EXTREME-1","price":334.0,"currency_code":"CAD","in_stock":true},{"title":"2\"","offer_id":43697369972965,"sku":"OL-L-EXTREME-2","price":432.0,"currency_code":"CAD","in_stock":true},{"title":"Nikon Z mirroless mount","offer_id":48076800622821,"sku":"OL-L-EXTREME-NK-Z","price":363.0,"currency_code":"CAD","in_stock":true},{"title":"EOS-R","offer_id":48076800655589,"sku":"OL-L-EXTREME-EOS-R","price":363.0,"currency_code":"CAD","in_stock":true},{"title":"Sony-FF","offer_id":48076800688357,"sku":"OL-L-EXTREME-S-FF","price":363.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0652\/6245\/2965\/files\/optolong-l-extreme-dual-band-filter-astronomy-plus-1.webp?v=1690487119","url":"https:\/\/istronomyplus.com\/products\/optolong-l-extreme-dual-band-narrow-band-filter-l-extreme","provider":"Astronomy Plus – Telescopes \u0026 Astrophotography Canada","version":"1.0","type":"link"}