My first reaction is that it's not tracking well. You might want to try PemPro to improve the periodic error. Then the guidance would have a better chance. Also, how long was the exposure? You should think about taking a series of short exposures and then stacking them, rather than longer exposures, because the error will be less for each image. Best wishes, Joe ________________________________ From: "gazebo4sale@comcast.net" <gazebo4sale@comcast.net> To: Utah Astronomy <utah-astronomy@mailman.xmission.com> Sent: Sunday, May 22, 2011 9:55 PM Subject: [Utah-astronomy] Whats Wrong With this Picture Dear Utah-Astronomy, I am just starting to learn to take some astropics and would love to get some input as to my mess so far. Each mess is a learning experience however. I am set up for Afocul Photography. the photo I am using to show my problems so far is at: http://home.comcast.net/~galico/Astropics/comae berenice.jpg It is an attempt to take a photo of NCG5024 (M53) the beautiful Open Cluster in Comea Berenice. This is a 500 second exposure Here is my equipment I am using for this shot. Celestron Nexstar GPS 11 with most current hand control software. Celestron Heavy Duty Tripod Celestron Heavy Duty Pro Wedge Canon, unmodified, Rebel XTI (10 MP) Shooting Through the Diagonal. CNC Wide Mouth T Adapter. Canon Remote Shutter Controll-Not a wireless. I was set up on a very clear night in Mesquite Nevada (Moderate Light Pollution). Coma Berenice was at about 65 Degrees ALT. I was set up on the lawn with antivabration pads. It was about 65 degrees F. I used the Nexstar Equatorial North Allighment technique, then I used the Polar Mount Alignment routine included in the Celestron Software. I used a 12.5 mm illuminated cross-hair reticule for polar alignment and I felt that the polar alignment was vis ually pretty good. I used the Precise Traking routine on the Celestron Hand Control-selecting Diadem as a guide star. Here is what I think is going on: There are tracks showing that I am not precisely polar allignd, but I have helix shapped tracks of the stars. The equitorial alignment is not good enough and the helix star tracks are the result of the telescope correcting itself in both ALT and RA. If it were just an allingment problem I don't think I would get the helix shapped tracks and I would just have arc shapped lines. I used 2nd mirror lockup and a cable attached shutter controll. Could there be vibration problems with my just tippi toeing around the telescope? There is a great deal of dark current shown which I guess is handled by software and/or having a modified camera. I think that if I shut off the GPS and used the RA only option, after using the Celestron routine, I could drift align the mount to a more precise alignment. Your input would be most appreciated. Thanks Steve Gallenson . _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.slas.us/gallery2/main.php