Hi everyone,
I have a Celestron Nexstar 6SE with a focus issue. I have had a look at the collimation screws of the front of the Nexstar and have attempted to adjust. all seems fine with the artificial star set up and checking secondary mirror collimation (distance of artificial star as per manual). The issue is when I used the primary mirror focuser (rubber knob focuser). I can get the stars and planets to focus to a point but often there is a flare off to the bottom left and even looking at the moon, while there is no flare it just makes your eyes attempt to adjust to a slightly out of focus moon. Adjusting the primary knob backwards and forwards to the extreme to come back to refocus seems to demonstrate the scope can focus to a point. For instance, the trapezium of stars in Orion I can make out the four stars but they are fuzzy and cannot get them to focus properly.
There are a few little smudges on the glass with the secondary mirror, but nothing too significant. Also I can only find advice on collimating the secondary mirror which I have worked through already.
I only bought this new, however I bought it from the US, so the warranty is not going to work.
Does anyone have any ideas, routines / processes or advice on what to try?
Cheers,
Matt