Even recent readers of this blog may not know of one of my old passions: building telescopes. Back when I was ten or eleven years old, I read an article in Popular Mechanics or some such that told how you could build a telescope from scratch, including grinding and polishing your own mirror (most amateurs build reflecting telescopes, where the primary optic is a mirror, rather than refracting telescopes which use lenses). Somehow, I conned my dad into beginning that as a project. We purchased a 6″ mirror kit from Edmund Scientific, and set to work.

Sadly, my dad was diagnosed with Hodgkin’s disease shortly after that, and passed away several years later. The telescope mirror sat unfinished in my mom’s closet for about fifteen years.

Until I moved to the SF Bay area in 1991, and learned of the Chabot Telescope Makers Workshop. They met up at the old Chabot Observatory every week, and under the leadership of mentor and friend Paul Zurakowski, hundreds of people learned about building and using telescope. I served as a volunteer instructor for a dozen or so years, helped hundreds of people on their projects, and did several of my own, until family commitments and such proved to be too much for me, and I stopped going, about five years ago.

And yet, I still am interested in it. Things are a bit smoother now than they were, so last night I decided to get up to the workshop and see what had changed. The answer is: not a heck of a lot. People are still showing up and building telescopes. A lot of the same people (Rich, Dave, Anthony, Mark, Alan) are showing up and carrying on in the same way they’ve been going on for years.

I brought in the project that I had going when I stopped: my 12.5″ f/5 telescope mirror. It was polished out, and I had begun figuring it, but it has sat on my shelf for more than five years untouched. I used the Ronchi tester that they have at the workshop to check out the general figure:

(Pardon the bad cell phone picture, but it conveys the right information). Most of you won’t understand what you are staring at, but even though I’ve been away from this for a long time, I can see that the figure is a bit rough, with a broad center zone which is a little bit “flat”, and the overall correction is a little bit overdone. I think it’s time to make a new lap and get working on this scope.

I’m not sure that I’m going to get up to the workshop every week like I used to, but I am going to try to get up their at least once a week, and to do a little bit of work on my telescope every week. I’m sure you’ll be reading more about it here. Stay tuned.