I’ve been a visual astronomer most of my life, but am wanting to learn AP as well. I have an 18" starmaster f/4.5 with an alt-az tracking/goto drive system on it and an ASI294MC Pro cooled CMOS camera. Up to this point I’ve just been playing around with live stacking short exposures, but I would like to see what I can do with stacking large amounts of frames but am being told that field rotation will become a factor at some point. When I googled ways to counter it, SGP and it’s manual rotation feature showed up, So I became interested in purchasing it. I did look at the SGP manual and found the section on manual camera rotation. In the example it shows, it somehow determines how far of the camera was off and then generated the amount of degrees it needed to be rotated. Buy how do I know how much to turn the camera to match the number of degrees it shows? does a grid show up on the screen and to give me a point of reference to know that I’ve rotated the camera the required number of degrees? and secondly, since my scope is a newtonian, will I be able to accurately line up the diffraction spikes on the stars or will the stacking software handle that?
Thanks in advance for any and all help,