Tried to shoot the Rosette Nebula a few nights back and was having focus or wind issues...not sure. See attached.
To me, it looks as if I'm having focus issues. However, I tried the same exact frames at 30s and 60s and seemed to be getting better, sharper images (HFR's as low as 1.02 at 30s, not 3.05 like you see below). Sadly, didn't save those subs for comparison to show you.
So, I'm wondering if the length of the exposures was the issue and wind was affecting it? Wouldn't wind issues show streaks or star trails, not blobby stars?
FYI, wind was light, but gusts of maybe 7-8mph from time to time.
- Could wind cause the issues you see in that sub?
- If it was focus (not wind), why were the shorter subs better than the longer? Can the focuser creep out of focus over the course of a 3m sub? And if so, why did subsequent 30s subs seem to look okay?
Thanks for any help or thoughts,