Hi Mike,
My approach may be naive, but it seems to work for me:
I approach RC collimation as 2 tasks - out of focus (OOF) roundness, and
centering the central OOF point.
I first Center the secondary using my eyes.
The the OOF roundness is adjusted with the collimation screws on the body of the telescope. Use a circle in your display to help get roundness correct.
Next adjust the secondary to Center in the image. When it gets close, you will see most of the OOF images are centered.
Here’s the type of resolution I am getting with my RC-8 carbon.
https://www.iceinspace.com.au/forum/...e.php?a=315489