Jared, I have tried longer exposure times as well but that is not helping either for some reason. SGP refuses to recognize some stars, maybe due to low contrast etc… for example, in the NGC4490 frame I have shared above, there are at least 4 more stars that SGP can use but for some reason these are not recognized as stars. Today is cloudy unfortunately but I will give this another chance with longer exposures.
Moving to another region for focusing is not an option here either. Platesolve 2 and Astrometry.net cannot solve these frames with so few stars and I’m centering the objects manualy, which takes quite a long time ( I’m operating this system remotely. The sluggish internet connection makes nudging the scope precisely a very difficult task).
Meanwhile, I would be more than happy working in Single star mode. [Edit] Being able to select a subframe for focusing, as CCDMan suggested above, would be a much better option though… if it is doable of course…otherwise, single star should yield much better results than the current situation in extreme cases like mine and spokeshave’s.
By the way, because this set up is way too oversampled, I’m using 4x4 binning for focusing and platesolving. Do you think this can contribute to the problem ? Working at 3910mm is a real challenge!