Centre spotting a primary

[lguise]

I want to centre spot a primary which has just been recoated and was wondering if anyone had an easy and accuate way to do this?

I have done it on a secondary before by making a paper mask, marking major and minor axis, pin hole where they cross and a tiny touch of a black pen through the hole on to the mirror. This works well. I was planning something similar for the Primary but wondered if anyone has a better method?

Many thanks,

Linton

[Beulah]

That's exactly the method I plan to use on my primary once it is ground and coated.

[Ben Ritchie]

I use this

http://www.catseyecollimation.com/15in%20Max%20Template.pdf

printed on clear acetate - makes life very easy

[lguise]

Ben,

Now that is a great help, many thanks

Linton