Thanks, Gary and Lee.
I think the secondary mount should not rotate, and doing so would definitely affect the collimation. ?That's why there's a registration notch, so the secondary will have the same position when put back. ?I looked at the cross section of the C14 Edge and it appears that the secondary mount is secured by a threaded lock ring on the inside of the corrector plate. ?I don't see a washer, but there might be one. ?If the washer is an elastomeric material, it could take a set and cause the looseness. ?I still have the same questions. ?Is the secondary mount tightened by simply holding the lock ring and turning the exterior cylindrical mount, and it the orientation of the secondary important, putting aside the collimation issue?
Thanks,
Don
