Re: [ATM] ronchi accuracy

[Michael Peck <mpeck1@ix.netcom.com>]

At 13:23 12/10/05, Mel Bartels wrote:


>I've been using the Ronchi test for 25 years.  I make better mirrors using
>the Ronchi test compared to using other tests.
>
>
>Not only do I need to test for all the above, but I also need a test that is
>reliable, consistent, accurate, inexpensive, easy and fast to use.
>Particularly in mirror making classes, the bottleneck is testing, when
>students line up, waiting for their mirror to be tested and analyzed.
>
>There's an amazing variety of tests to select from.  Some are easier to use,
>some are more predictable, some are more accurate, and some are more
>expensive.  Many tests use math.  Most Americans are mathematically
>illiterate.  To recommend a math intensive test is to tell many that mirror
>making is beyond them.
>

Have you considered building an interferometer for class use? If not, why not?

Just one comment for now. Any optical test involves mathematics. 
Generating theoretical ronchi patterns for comparison is a highly 
mathematical  and computationally intensive exercise, especially if 
you do it right. So it seems to me regardless of the test the 
mathematically illiterate have to rely on the work of the 
mathematically literate. Since the mathematically literate have 
produced free software for the analysis of just about any optical 
test you can think of mathematical illiteracy shouldn't be an 
obstacle to the use of better tests.

Mike


_________________

Michael Peck
email mpeck1@ix.netcom.com
Wildlife photoblog http://wildlife-pix.com
Amateur telescope making http://home.earthlink.net/~mlpeck54/astro/astro.html 

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