[bugeater (Marty)]

So I picked up a TS 9mm OAG in the classifieds and have set it all up with my QHY5L-II. This camera worked fine with a little 50mm f/3.25 guidescope, but I want to eliminate as many guiding issues as possible, including differential flexure.

Took me a lot of messing around to get everything joined properly - why on earth can't Baader produce a proper instruction manual for their MPCC? I couldn't attach the MPCC to the OAG without an adapter and then the backfocus difference was all wrong. Only after a lot of messing around did I work out that an inner set of threads could be unscrewed from the whole thing to get the backfocus right, but none of Baader's material indicated this was possible. I even found posts where people were machining these threads off because they were fouling on the prism in the OAG.

Anyway, after all this I got it outside and have found it tricky to get working particularly well. I guess I'm used to the pinpoint stars of the guidescope, but they look large and bloated at best in the OAG. This is normal right? My setup has a focal length of 1000mm, so I guess the magnification is greater. I've tried to see how good the focus can get with just the main focuser, and I think I'm close to parfocal with the main camera.

Also the guide image is pretty flaky. Does anyone have some QHY5L-II settings that work for them? If there is a brightish star in the image, then everything seems okay, but if there are only faint stars the image becomes really noisy and it's impossible to do any guiding. I'm also lucky if there is one star to chose from. I guess the light pollution filter won't help, but I can't see how that can be moved.

I really want to use this thing, but so far it's been difficult. Any hints or tips to help me on this journey would be appreciated.