Once again ... many thanks.
rumples: I've been eyeing that book off for a few weeks now. May make a purchase, even if there's nothing wrong with my Skywatcher. I agree it would make for interesting reading and be a real handy resource up on the bookshelf.
starkler: you put my mind a little more at ease. It never dawned on me anything less than great seeing could result in different star test results when comparing inside and outside focus? I just assumed that if I was getting nice diffraction rings outside focus I'd get the same image inside, assuming there was nothing wrong with my primary? If you're right, it's a great way to get a quick gauge of what the seeing's like? It's a seeing "tester"!!! lol
