[mike geisel]

Hi, thanks for the replies. Glen, I was interested in your comment that the 1600mm-c would be fine at anything below 10deg. I always try and get it as cold as possible, but I also read somewhere recently that it was more important to keep the temp constant. At the moment I have it set to -26deg but maybe in the hot weather I should be more realistic and set it to something like -14deg. Also one of my biggest problems with astrophotography is patience!. 3 hours total on this was all I could bear. Your suggestion of 3x100 subs at 5min would drive me insane!
Malcolm, thanks also. I have my gear permanently set up and aligned in an observatory and thought the polar alignment was pretty good, within a few arc minutes. But I think I will revisit this and see if I can get better. I use Sharp Cap pro for capture and it has an automatic apply darks feature, but I think the dark files need updating, so I will try that. I have been lazy and slack and not doing flats and biases and up until now have been getting away with it, because subs have been fairly short, usually 60 seconds. I plan to start using these calibration frames soon. Perhaps the lack of flats is the reason for the background streaks? I do alignment usually in Nebulosity 4 and at the moment only use pixinsight for modified hubble colour correction. But I hope to learn more about pixinsight over the next year, (New Years Resolution??) Thanks guys
Mike