To: atm{at}shore.net
From: tkrajci{at}san.osd.mil
Reply-To: tkrajci{at}san.osd.mil


> From: "Jerald F. Wright" 

>     I used the Focault and Ronchi tests.

That's a start, but we need specifics here.  Any comment on light source?
moving?  fixed?  slit?  pinhole?  dimensions?  Couder mask?  pin stick? 
how many zones?  Any photos, diagrams, etc. of your test rig that we can
see?

> I have tested mirrors better than
> 1/40 wave and could still see the errors with the old mark IV eyeball
> without too much difficulty.

We need specifics.  So far you have not provided anything to an ATM where
one could then say "yes, now I know what I have to do to change my
testing procedures to improve accuracy and precision.  I also know what I
have to do to confirm/validate my improved accuracy and precision."

Can you add anything specific such as:

- In order to reliably measure to 1/40th wave...your test stand needs to have
motion repeatability on the order of X inches.

- You can't say you have measured 1/40th wave with confidence until you have
made Y measurements of Z zones, with a standard devation of Q or less.

> On the Astroscan mirror there was no detectable
> error at all. It was well beyond the sesitivity of the test. How sensitive
> are the tests?  Different for different people and test rigs.

How can any ATM's use your vague advice to improve and change their testing
procedures?  Please give us specific information that folks can use and
duplicate.

Tom Krajci
Tashkent, Uzbekistan

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