[RussellH]

So I was going down the path of getting an OAG instead of a finder scope for my auto guiding.

For Pro’s, I was impressed with the extra guiding accuracy that OAG’s provide, which is important for imaging, not having to match images with a guide scope for pointing accuracy and reduced weight in the mount.

Con’s I knew of are focussing difficulties, careful alignment of the prism so as not to block the image sensor, the limited field view being picked up by the guide camera and possible image distortion and the extremes of the field of view.

However, I’ve just had the big realisation that if I can’t feed a live view of my camera (Canon M50) into whatever software I end up using, then the limited field view to the guiding camera is probably going to make it impossible to use any of the automation tools to get my polar alignment as accurate as possible for long exposures. The seems a bit of a show-stopper, as without accurate PA, everything else falls apart.

Does that sounds right? I’m still researching all the various methods of PA through PHD, Ekos/Stellarmate, AISAir or the other numerous software solutions, but I’d think they’d all want an image with a decent FoV to resolve where things are pointing at, would’t they?

All that aside, have I missed any other gotchas for OAG’s? Does anyone with an OAG also use a finder scope as well, to try and ge the best of both worlds, assuming the software even allows swapping between multiple cameras for different functions?

Thanks.
Russell.