I got out about 11pm and took a little extra time setting up and polar aligning. As always, I do a simple one-star alignment of the scope and then go to "Precise Goto" in the menu. Normally it will put the object somewhere near the center of the camera's field of view...often dead center. Then, if necessary, I will make some final adjustments of the object's position and begin the focusing process. "Fine focus" in Nebulosity works pretty well. Moving to another object is usually a matter "Precise Goto" again, and a brief re-focus. It works well.
I took some preliminary shots of M29 and then moved on to NGC 891, attached the StarShoot and got PHD guiding up and running.
* I set 3 minute exposures and set the camera for 55 subs. The first 5 or six frames looked great and my guide graph stayed within one pixel. Then for some unknown reason every 5-6 frames after that, the declination axis line would jump straight up 3 pixels, and then drop back down. Each time it happened, it looked exactly the same on the graph......always up, and always corrected immediately. As a result, I threw out 5 frames.....useing 50. The five I threw out were grossly double-imaged.
Strange, without guiding assistance, the mount will track pretty well for 3 minutes...sometimes allowing a slight drift....but more often providing sharp image frames. For some reason, the guide software and the mount don't like each other. The screen capture is representative of the way it behaved.....most like the far right with a rise or dip of about one pixel.....all except the occasional upward spikes. Puzzling.
Equipment: Orion 6" f/5 Newtonian
Celestron CG5 GT mount (guided)
Canon 350D (unmodified)
Software: Deep Sky Stacker
Photo Shop Elements with Carboni tools & Gradient Exterminator
NGC 891: 2 1/2 hours (50 x 180 seconds)