But none of these worries seem be justified:
My guiding error is constantly <0.5 pixels (on the Lodestar) - mostly < 0.4. That's less then 1".
- Flatness of the image
Here is the CCDInspector analysis for some of my images:
3% tilt is pretty good. But it's weird that the image is tilted to one side. Here is another curvature plot from images that were taken on the other side of the mount:
It seems as if my imaging train is somewhat susceptible to tilting. But again only a little bit. The image itself doesn't show any curvature in the edges!
- And finally polar alignment (and also flatness) of the image. Here are magnifications from the 4 corners of my image of the Rosette Nebula:
What can I say? Round, pointy stars all around. No elongation into the corners (flatness) and no elongation around the center (field rotation)
Very, very good. I can now setup my scope. Do a quick polar alignment with the RAPAS - and off I go!