[ATM] Phase contrast and the 10 incher.

[Stephen Koehler]

Arjan,

> Have you tried the mirror in your interferometer?

I have a couple of interferograms from Dale of this mirror that I will
attempt to analyze, looking for any evidence of the high-frequency
detail seen in the phase contrast pictures.  I'm not hopeful, because
the interferograms are not of very high quality.  (Something went
wrong with Dale's interferometer when he traveled with it to Seattle,
recently.)  I will try to do this today.  My plan is to analyze them
using the FT method with a large filter (either a half-plane filter
or, if possible, the vortex method).  From the resulting wavefront, I
will extract the high-frequency content.  The question is whether
enough high-frequency information is in the interferograms, and
whether it can be seen through the noise.

-- 
Steve Koehler