Had another attempt with the Ha filter last night, this time on the Horse Head neb. Got off to a slow start with a band of clouds rolling through just as the object crossed the meridian. I managed 160 mins in 10 min subs before the next cloud band came through at which point I packed it in. On inspection of the subs I found the last 6 were spoiled by dew forming on the CCD
. I can't understand why this is forming late in the imaging run?
Anyway here is is 10X10mins using the QHY8pro and 10". I'm not entirely happy with the star shape on the brighter stars either. I don't think it is a colimation issue as I carefully checked this before starting.
Comments/suggestions welcome.
Thanks flor looking.