{"id":115,"date":"2008-10-24T13:30:50","date_gmt":"2008-10-24T13:30:50","guid":{"rendered":"http:\/\/www.steves-astro.com\/?p=115"},"modified":"2008-10-24T13:30:50","modified_gmt":"2008-10-24T13:30:50","slug":"ic1805-heart-nebula-with-new-baader-35nm-ha-filter","status":"publish","type":"post","link":"https:\/\/www.steves-astro.com\/?p=115","title":{"rendered":"IC1805 Heart Nebula, with new Baader 35nm Ha filter"},"content":{"rendered":"<p>One of the issues with imaging with the Hyperstar @ f\/2 is that the wavelengths all get shifted by ~6nm, so doing narrowband with it can cause some real issues. A 13nm filter would appear to be OK, but in fact by the time (for example) Hydrogen Alpha is shifted by 6nm, its in the 30% or less bandpass section of the filter.<\/p>\n<p>Then Baader released their new range of filters, including an oddity&#8230; a 35nm Ha filter. Is it a wide Ha or a narrow red? Who knows, but its use on the Hyperstar was obvious to me, keeping the peak Ha emision line well above the 90% transmission. It also seem to cope really well with the full f\/2 shift at the outer egdes of the QHY8 APS size CCD. The only small downside is that because of the wide bandpass, its not quite as &#8220;contrasty&#8221; as you would expect from a narrowband filter.<\/p>\n<p>So, here goes:<\/p>\n<p>OTA: NS8GPS @ f\/2 (Hyperstar v3)<br \/>\nGuiding: William Optics ZenithStar 66 SD + DSI-C + PHD<br \/>\nImaging: QHY8 + MaximDL, 24\u00c3\u2014600s, Baader 35nm Ha<br \/>\nStacked: DeepSkyStacker<br \/>\nPost Process: ImagesPlus + PSCS2 + Noel Carboni\u00e2\u20ac\u2122s AstroTools<\/p>\n<p style=\"text-align: center;\">(Click on image for larger version)<\/p>\n<p style=\"text-align: center;\"><a href=\"\/images\/ic\/ic1805_ha35nm_20081021_full.jpg\"><img decoding=\"async\" loading=\"lazy\" class=\"aligncenter\" src=\"\/images\/ic\/ic1805_ha35nm_20081021_800.jpg\" alt=\"\" width=\"800\" height=\"531\" \/><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>One of the issues with imaging with the Hyperstar @ f\/2 is that the wavelengths all get shifted by ~6nm, so doing narrowband with it can cause some real issues. A 13nm filter would appear to be OK, but in fact by the time (for example) Hydrogen Alpha is shifted by 6nm, its in the [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[4],"tags":[],"_links":{"self":[{"href":"https:\/\/www.steves-astro.com\/index.php?rest_route=\/wp\/v2\/posts\/115"}],"collection":[{"href":"https:\/\/www.steves-astro.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.steves-astro.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.steves-astro.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.steves-astro.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=115"}],"version-history":[{"count":3,"href":"https:\/\/www.steves-astro.com\/index.php?rest_route=\/wp\/v2\/posts\/115\/revisions"}],"predecessor-version":[{"id":118,"href":"https:\/\/www.steves-astro.com\/index.php?rest_route=\/wp\/v2\/posts\/115\/revisions\/118"}],"wp:attachment":[{"href":"https:\/\/www.steves-astro.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=115"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.steves-astro.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=115"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.steves-astro.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=115"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}