Crimped Optics

[Shelster1973]

Is it possible to have a crimped primary because you have tightened the collomation holding screws down too tight?

Was out last night for the 1st timein ages and noticed that I was getting none round stars, even at centre of image.  I removed the retaining brackets a while back so primary is held in place by silicone blobs, so know this cannot be causing the issue, so the only option left is that I have over tightened when finishing my collimation.

[Alkaid]

Yep, the primary holding screws just need to be applied very gently.  Don't torque them up.  I normally turn them until I just feel initial resistance, then stop.

[Shelster1973]

Will be backing them off tonight then...many thanks

Have been thinking of putting some large plastic washers underneath them too so as to spread any load they place on the primary....but this may just be my tinker bug coming to the fore again