Focus IssuePosted By Howard Platnick |
I have a SCT 8 inch Celestar and have been looking at saturn with a 26mm plossal and a 2x barlow. I take out the scope an hour before observing to allow it to cool down. I think it is collumated, as when I de-focus on a bright test star the ring looks symetrical. Saturn comes into sharp focus and stays that way for just a few seconds and then it becomes fuzzy and stays fuzzy until I re-focus. This keeps happening.
Any ideas why and what I need to do to correct it?
much appreciated Howard
Any ideas why and what I need to do to correct it?
much appreciated Howard