Sharpcap live stacking - alignment issues

Discussion of using SharpCap for Deep Sky Imaging
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oopfan
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Re: Sharpcap live stacking - alignment issues

#11

Post by oopfan »

Dave (turfpit) brings up a good point for you to be aware of regarding Alt-Az mounts. Field rotation over, say, 30 minutes leads to an image having noticeably rounded corners. IMO, I don't see this as a huge problem since the RedCat has a large FOV. However, if you are imaging something large that fills the frame, then you should LiveStack for 30 minutes, stop and save the stack to your HD, and then immediately start the next stack. Minos Kritikos pioneered this work, seen here:
https://www.astrobin.com/330099/

EDIT: You will need to do an initial Plate Solve just before starting the first stack. Take note of the camera's rotation angle. Thirty minutes later, after the first stack is finished, perform another Plate Solve. The rotation angle should be several degrees from the previous Plate Solve. Use the RedCat's Field Rotator Ring to bring the rotation angle inline with the previous angle. Then, start the new stack. Rinse and repeat until you are exhausted.

Brian
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