The Double Cluster

21:24 19/8/2005 UTC

Full moon was up and still I couldn't resist doing some imaging. I had to choose some bright open cluster to my target to manage the background sky glow. Not everything went well with this image... I'm not sure what went wrong with polar alignment, but I got severe field rotation. IRIS couples with that easily. But I had to throw 19 frames out, because of tracking errors. Also I think I overexposed the image a bit and got huge chromatic aberration. To battle with that I took luminance channel from red and green only. Still its a lot better than my first visit with the A70.

NGC/IC Object List:
NGC869 open cluster RA:02h19m03.7 Dec:+57°08m'06" BMag: , OCL 350 H Persei, Double Cluster
NGC884 open cluster RA:02h22m32.0 Dec:+57°08m'39" BMag: , OCL 353 Chi Persei, Double Cluster

Camera: Canon EOS 350D (Rebel XT) | Telescope: William Optics Zenithstar 66mm f6 petzval refractor | Mount: Orion Skyview Pro, Boxdoerfer PowerFlex MTS-3SLP drive controller | Filters: - | Guiding: Orion ShortTube 80mm f5 refractor, Phillips ToUCam Pro II webcam, Qastrocam, Orion Shorty Plus 2x Barlow | Exposure: 6 x 90s (9m) f6 ISO400 | Software: IRIS, GIMP | Location: 60°31'N 26°52'E (Koivula/Kotka,FI) | Image Field: 2.463 x 1.849 degrees | Image Center: Ra 02h20m44s Dec +57°03'36" | Target altitude in the beginning of the exposure 51°