[Geoff45 (Geoff)]

Here are three pics of NGC 1365 from the same set of raw files. The problem was stupid error#27 in my list of stupid errors--forgetting to switch the moving speed of the mount from visual to photographic. The stars are pretty much all over the place when I did a straight align and average combine in ImagesPlus (left pic). Also there is a satellite trail in one of the frames, which still shows in the combine. So I tried a different combine method--Sigma clipped average in ImagesPlus. This basically throws out the outliers for each pixel and averages the rest, so the satellite trial goes and since the tracking errors are random, most of them appear as outliers and so the result (middle pic)is better. I then found the best 4 frames (out of ten), sigma combined them and pasted them as a layer over the middle pic with the blending mode set to darken. This got rid of a few more tracking errors. Next was to round off the stars a bit in the usual way and finally to remove the gradient, using Russel Croman's Gradient Xterminator plug-in for Photoshop (well worth getting at about $40).
The final result (right pic), while not the greatest pic in the world is still presentable.
Geoff