1: Another Great Book For Mirror Makers
When I got into making my 16" mirror in the 80's, though I had the book by Allyn J. Thompson, I wanted something more up to date. I'd thought of the Jean Texereau book but was scared away by the math (I've since learned it wasn't as bad as I thought it would be). So, I saw this book in Willmann Bell and ordered it. It was a real treat to get it as I was living in Spain at the time and books like this were not available in the base bookstore.
The book is very well laid out and informative. The instructions are simple and not overly technical. It was a real pleasure to have this book as a guide because it covered larger mirrors that the Thompson book didn't. It worked great until I got to the mirror testing part, and had trouble with the Focault testing because I was having problems with astigmatism. My mirror was quite thin, and I wasn't used to the extreme shadows I was seeing. A friend in Minneapolis St. Paul came to the rescue and sent me a Ronchi grating of the proper spacing. The lines on my mirror looked like a butterfly! No wonder the Focault shadows didn't look right! In that respect, the book didn't help, but once I got the lines straighter, the Focault method Howard outlines works just fine.
This book also has a lot of extra stuff that really came in handy when it came to making the scope after the mirror was done. Howard did a great job and this is another book to add to your library if you are at all interested in mirror making. Highly recommended.
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