[OzRob (Rob)]

I am posting this just in case someone else finds the same problem.

I had noticed that on some nights my stars were deformed. It appear that there was an in focus image of a star merged with an out of focus image of the same star (see the attached image.) The alignment of the two was the same across the whole field of view.

What I found was that the lens cell was not tight and I assume it allowed some slop. After tightening the cell the issue was resolved and I am sure that the stars are tighter than they have been in the past.