having experience with Newtonians and related instruments since long, I have developed a maybe new method for collimating them especially for imaging.
There is a basic collimation with laser, and finetuning systematically using the startest and the symmetry of offaxis aberrations, and with the camera as a measuring device.
That means the collimation is done with the very equipment you use for your photography, and therefore optimized for that.
I have described everything somewhat lengthy maybe, but for the sake to instruct newbies to the topics as well.
I had great success using it for Takahashi Epsilon Astrographs, too.
First I developed it when finetinung the field correction of some FSQ106 samples that had problems with star forms at the corners.
So I think the method is applicable to any imaging system, if you know how to adjust them.
Hope it helps you! Your feedback is welcome!
Edited by tommy_nawratil, 09 April 2021 - 02:28 PM.