I have now noticed, that the CCD-chip in my QHY9 is not perfectly orthogonal to an optical axel.
When fast focal ratios are used this comes more obivious, stars are not in focus in the other side of the image.
CCD-inspector tels me the same story.
Is there a method to adjust this or do I have to make up a DIY solution?
Has anyone else noticed a similar problem?
It has to be the chip, since camera rotation rotates the problem as well.