While I drew inspiration from many sources, these are the references upon which the telescope's design was ultimately based on.
The Dobsonian Telescope by Dave Kriege and Richard Berry. I bought this book mostly because Richard Berry is a kind of a personal hero of mine. A friend gave me a copy of Astronomy magazine when I was 13 and it ignited a serious interest in astronomy I have had ever since. Having read every issue of his "Telescope Making" magazine, I have long wanted to put the knowledge learned there to use. In addition, "Telescope Making" documented the move of the Dob into the main stream of telescope building and so it left me with the lingering desire to build not just any telescope, but to build a Dob.
I cannot recommend it enough. Del teased me for my repeated references to it by calling it my "bible". It taught me the rules and why the rules exist, so I knew when and how I could break them. When designing a scope to fit a non-standard need, it was great to have a reference standard to use for all the variables I didn't want to have to learn by trial and error. Stuff like "How thick do the walls of the mirror box need to be?" or "What diameter truss tubes do I need?" By knowing the answers to these mundane questions, I was free to worry about the real issues of trying to squeeze a 15" scope in a tiny trunk. Answers that seem obvious only in hindsight. On top of all that, there are just a lot of great tips and tricks learned by experience.
Dale Keller's Newt was invaluable for calculating things like vignetting of the 75% light ray and how much contrast reduction there would be for a given secondary mirror size. It was nice to also have confirmation of my math for the secondary mirror size. I found myself playing with numbers for iteration after iteration just to see how each tweak would affect the final performance.
Cell by Dave Chandler, is the classic mirror cell layout program. Unfortunately, it doesn't run in the DOS window on newer PCs. I had to track down a machine running Win95 for me to get it to work. On newer machines I keep getting run time errors.
Plop is by mirror cell design program by David Lewis and Toshimi Taki. It is a really slick program using the latest in mirror cell design theory to produce the optimal support layout. As such, I wish I had used Plop instead of Cell. What happened though is that I did some back of the envelope calculations that contradicted Plop and lost faith in it. After I finished the scope I sent a bug report to David Lewis with my reasons why I thought there was a problem in Plop. To my amazement he promptly got back to me and showed me the errors in my calcs. If I get the chance I will recut the support triangles to match what Plop suggests.
An additional benefit of using Plop had to do with knowing if I needed a 9 or 18-point mirror cell. One of the rules on thumb in the Kriege and Berry lead me to worry that my relatively thin mirror should have an 18-point cell. Unfortunately, I didn't see plans for an 18-point, 15" mirror cell in the book. Plop helped give me confidence that 9-point mirror cell would work.
Johan Vanbeselaeres Mirror cell design help along with the results from Plop made me believe that I could get away with a 9-point mirror cell.
I always hoped that I would be able to include digital setting circles in the Miatascope. Doing so required that they be included in the design right from the start. In particular, I needed to know how high the azimuth encoder would be above the pivot bolt. I found this site to be very helpful in making my decision about which digital setting circles to buy.
Back to the Miatascope home page.
Last updated 4/16/06