I have been using SGP for years. I have a Pegasus Falcon rotator that I have been using with Ver 4.4 with no problems. I just updated to ver 4.5 and found that there is a difference with how the plavesolving works with the rotator.
Previously with ver 4.4 I would use ‘Framing and Mosiac wizard’ to determine the placement of the imaging window, including adjusting the angle. I then use ASTAP to preform the platesolving. When I use ASTAP it would first take an image, solve the image and determine the pointing and angle error (for example it would determine there is a pointing error of 1,200 pixels and an angle error of 43 degrees). It would then command the rotator to correct the angle error and the mount to correct the position error, and then take another image. It would continue to do this until the position error is less than 50 pixels and the angle error is less than 1 degree. It would normally take 2 or 3 attempts ta most.
I recently upgraded to ver 4.5 and find that platesolving is different. It first commands the rotator to adjust the angle and the mount to the prescribed location (before it even has taken a single image) and then takes an image. The result is a slight error in position but always no error in angle. SGP then commands the mount to correct the position error and takes another image. SGP usually meets the prescribed error limit on the 2nd attempt without adjusting the angle. I do not understand how platesolving could acquire the exact angle without first taking an image to determine the angle error? Is there a setting that needs to be adjusted such as mechanical versus sky angle? The result does seem to be the correct angle so I know platesolve is actually working.