Expert: Paul Wagner - 5/6/2005

Question
I recently purchased a used Vixen 90mm Flourite APO Refractor, and I noticed that there are collimation screws on the objective. My question is , since it did not come with a manual, how do you adjust these three sets of screws? Each set is 60 degrees apart and has a long and a short screw. I don't have a laser collimating eyepiece, do you recommend one? I have a regular collimating eyepiece, without crosshairs. I messed with these screws, and I think that I has gotten it out of collimation. Also, how can I tell if the focuser is aligned with the tube? The objective lens has a little daylight on one edge, and does not seem to be square on. Thanks in advance for your help.

Dan Valentino

Answer
Dear Dan:

First of all--most refractors don't ever require collimation...that's one of their big advantages.  But once they get out of collimation, it is not something that the average amateur can tackle...

I do have two websites you could contact.  
One is the Vixen site itself:

http://www.telescopes-astronomy.com.au/vixen150.htm

The other is Company 7--a great organization with great service.  I would give them a call or drop them an e-mail...

http://www.company7.com/vixen/telescopes/vixen102fl.html

Sorry that I can't talk you through the process myself...

Paul Wagner