Good book on Star Testing your Scope

I have a 8" f6 and have tried to collminate it the best that I can with a Chesire. (A) I am looking for books that show me how to do star test with my scope to further fine tune my collumation...etc.

(B) Also, I heard of a trick where you put a mask with 2 large holes equal distant fron the center and look through your scope. I think that the idea here is to look through the scope and see if the 2 holes only appear as on hole. IF so you are in perfect collmination. Does this work?

Thanks, Steve B

The ultimate star testing book is "Star Testing Astronomical Telescopes" by Suiter. You can find it at http://www.willbell.com/tm/index.htm and it is one thing I didn't get for Christmas even though I asked for it!

The two hole mask I believe is used as a focusing aid for astrophotography.

Mark Bernhardt

The two hole mask is not used for collimation. It is used for focusing. When you have a camera attached to the back end of your scope its very difficult to see best focus thru the camera viewfinder. Put the mask over the objective, focus the two wholes until they appear as one, take the mask off and you are ready to go.

Suiter's book ia not easy to find. You can try the "available used" option on Amazon. That's how I got mine. It's brand new.

edz