Cheshire eyepiece: seeing the focuser drawtube!

[vanwonky (Dave)]

My cheshire arrived yesterday to add to my arsenal of collimating devices! But looking down it I can see one side of the focuser drawtube in view i.e the cheshire is in no way aligned straight down the tube. Loosening the 2" adaptor thumbscrews I can adjust it to where it should be but of course that is not much use.

Collimating is not really going to work using it in that state and this would (might) explain why Hotech laser is so far out when I think I have things looking good using the collimation cap.

Any ideas what might be going on? How can I get that 2" adaptor correct. Using my pea brain I imagine this is not a focuser / OTA alignment issue.

Might just have a Bex and a nice lie down instead

[jjjnettie (Jeanette)]

This might help I hope.
http://www.astro-baby.com/collimatio...on%20guide.htm

[asimov (John)]

You might have to shim your focuser into the correct position first. Making sure that 2" adapter is seated nicely of course.

[vanwonky (Dave)]

Thanks JJJ - I have read articles until my eyes bled. Pretty sure that one doesn't talk about this problem. But I might be wrong!

Originally Posted by asimov

You might have to shim your focuser into the correct position first. Making sure that 2" adapter is seated nicely of course.

I think until I get that 2" sitting correctly any shimming will be pointless. Hmmm..that is what you just said.