To: "Chris Feller" 
From: Scott Rychnovsky 
Cc: atm{at}shore.net
Reply-To: Scott Rychnovsky 


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Chris,

It might help to plug the numbers into sixtests and see what the calculated
deviation is from a sphere.  My guess is that you may be close enough to be
useful.  I find knife-edge measurements more useful than just saying that
it nulls with a knife edge or that the Ronchi lines are straight:
knife-edge measurements are quantitative.

I would also suggest using a point source (ball bearing and remote light
source) to examine the diffraction pattern at high power. Texereau
describes this setup in his astigmatism test.   You can look
inside and out of focus for equal Fresnel rings and check for a TDE very
easily using this method.  If you are carful to align everything you can
also check for astigmatism--which is certainly worth doing for your
reference optics.  Rough optics will also become apparent in this test.

Good luck with your project.

Scott



--
--
Scott Rychnovsky
srychnov{at}chem.ps.uci.edu
ATM Page: http://tlepage.home.mindspring.com/
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Re: ATM Waineo null test sphere figure
question
Chris,

It might help to plug the numbers into sixtests and see what the
calculated deviation is from a sphere.  My guess is that you may
be close enough to be useful.  I find knife-edge measurements more
useful than just saying that it nulls with a knife edge or that the Ronchi
lines are straight: knife-edge measurements are
quantitative.

I would also suggest using a point source (ball bearing and
remote light source) to examine the diffraction pattern at high
power.  Texereau describes this setup in his astigmatism
test.   You can look inside and out of focus for equal
Fresnel rings and check for a TDE very easily using this method. 
If you are carful to align everything you can also check for
astigmatism--which is certainly worth doing for your reference
optics.  Rough optics will also become apparent in this test.


Good luck with your project.

Scott



--

--
Scott Rychnovsky
srychnov{at}chem.ps.uci.edu
ATM Page: http://tlepage.home.mindspring.com/;


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