Question re Collimation

[shaneaust]

Hi:

I've attached a drawing I made of what I'm looking at now with my almost-collimated scope. Assume everything is centred except the innermost circle, and assume the centre-point marker is on the primary mirror..

I assume the inner-most circle is the primary mirror - what collimation technique/knobs do I use to line this one up as well? Having great difficulties in doing this!

We look like having perfect skies tonite...so a quick response(s) would be really GREATLY appreciated!

Thanks, guys!

[DobDobDob]

I can't answer your question, but given your diagram is accurate, I admire your zeal for perfection :thumbsup:

[taminga16]

Shane, have a look at this site, re;collimation.

http://www.andysshotglass.com/introduction.html

Regards GREG

[Geoff45]

Centre the innermost circle with the screws on the back of the mirror. Don't worry about the middle circle not being centred.
Have a look here http://www.atmsite.org/contrib/Carlin/collimation/ and at the attached pic. Note that the reflection of the secondary is not concentric with the other circles. (If you draw a large scale diagram of what the light path looks like for a short focal length, you can see why this is so)
Geoff