Just received an OCAL 4.0 electronic collimator for use with my EdgeHD 8 SCT. It seems to be a straightforward process, but I am seeing something strange in the tube. In case you are not familiar, the OCAL is a camera that sits in your imaging train and looks at the secondary mirror and presents concentric circles that you can use to dial in your secondary mirror for collimation.
My problem is my secondary mirror doesn't look perfectly circular in the camera. If I look closely, I can see what I think is part of the tube that the secondary mirror sits in in the OCAL image. I will upload a pic later if I can get one. Imagine if you were looking down an empty paper towel roll and they rotated it a few degrees. Thats the best way I can describe it. To me it looks like the secondary mirror is angled. Because of that I can't collimate it with the OCAL properly.
Does this sound like a case where my secondary mirror is not centered on my primary? If so, I know how to adjust it with the Torx screws but how would I know I am adjusting it properly? Is there any way to measure if or how far your secondary is off center?
Thank in advance!
Gene
Edited by GSquarePA, 09 June 2025 - 11:28 AM.
