If it's been 20 years, it's time to clean your mirrors. That's a subject unto itself, don't try it without learning about cleaning first-surface mirrors beforehand. The Odyssey telescopes can be frustrating to collimate due to the oversimplified optical supports. If you can bring it to a star-party, I'd be happy to take a look and help you tweek the collimation, if needed (and it probably does need it). We can help you clean your optics as well. On Wed, Apr 23, 2008 at 11:48 AM, Raeburn Kennard <rkennard@kmclaw.com> wrote:
This discussion of collimation has been fascinating! I've owned my 10" Odyssey Dobsonian for almost 20 years, and I have never collimated it, unless I did so when I first got it (which I definitely cannot remember). Indeed, I'm sure I wouldn't know how to begin - even after reading all of these wonderful posts.