Best Collimating Tool Is...?

I'm somewhat bewildered by the various collimation tools available. I have an Orion XT8 Dob & am curious-laser, cheshire, what works best?

-Chas Argent

Quick and dirty? A laser collimator.
For Real Precision? A star.

--
Scott Baker
Vice President, New Member Mentor
San Diego Astronomy Association
http://www.sdaa.org
International Dark-Sky Association
http://www.darksky.org
Personal web page: www.starcrwzr.com

I use a single-beam laser for the secondary, a Rigel Aline tool for the primary, and a sight tube of my own make to re-check the secondary positioning.
--
Mike

Laser for secondary, barlowed laser for primary.

Sphing!

Clear skies,

Tom

I will occasionally use a Tectron sight tube to get the basic alignment of my dobs close to where I want it. Since my scopes are usually set up in the garage it's not really needed, but if I take them apart and transport them, then the sight tube may get used as a quick check. But I hardly ever use it once the secondary is set correctly.

I then use a 2" Kendrick laser to tweak the secondary position, and then I tweak the primary mirror so that the beam returns exactly onto itself. I do mean exactly too. That seems to be key.

Then I check with an autocollimator and tweak as needed. If I end up doing a lot of tweaking at this stage I run through the laser-autocollimator cycle again.

I've found that using a 1 1/4" Cheshire only makes things worse for me - there is enough slop when using a 1 1/4" Cheshire in a 2" to 1 1/4" adapter in the focuser that it gives me incorrect readings. So I skip that step - and I've proven to myself that I get excellent collimation without it. A 2" Cheshire is definitely superior - I believe that the Catseye guy makes them.

Doug