Best Auto Collimator Tool

[Jethro777]

I have a 10" GSO Dob, and want to make sure it is fine-tuned.
What exactly do I need? The manufacturers don't exactly make it easy. The GSO one has a 2" focuser, and I have a 1.25" adaptor of course.

I understand there is the catseye American version, and the Astrosystems one.

[rrussell1962]

I have found that my Catseye autocollimator gives far better results than my Farpoint one. I have never used the Astrosystems autocollimator.

[Jethro777]

I'm not familiar with the "farpoint" one? What is it?

[rrussell1962]

Hi Jethro, I was referring to the Farpoint autocollimator tool. Basically the same design as the Catseye one but not quite as precisely machined (at least mine does not seem to be) I was going by the title of your post. All the auto collimators I have seen are the same design - essentially a sight tube with a reflective surface under the pupil hole which allow more precise collimation of the secondary and primary by use of multiple reflections of the primary centre spot. Not to be confused with a simple sight tube and Cheshire.