[ATM] building a refracting telescope - willmann-bell

[Guy Brandenburg <gfbrandenburg@yahoo.com>]

I just got my copy yesterday of the new Willmann-Bell book on making your own refractor - much earlier than I expected. The book looks pretty thorough. 

After looking at the section on testing, I am glad that I'm making a Lurie-Houghton instead - the steps for testing of the LH are much, much easier, it seems to me. After all, every one of the 4 corrector-plate surfaces exactly matches another one, and half of them are concave, and the concave surfaces are easy to test, and a monochromatic light box allows you to test the convex against the concave. No such shortcuts on a standard refractor.


Guy


"Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved."
- wtote Charles Darwin.
Guy Brandenburg, Washington, DC
My home page on astronomy, mathematics, education:
http://home.earthlink.net/~gfbranden/GFB_Home_Page.html
or else 
http://tinyurl.com/r6fh2
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