Re: [ATM] Foucault images

[Mike Lockwood <melockwo@uiuc.edu>]

Dale,

Dale Eason wrote:
> I get isolated streeks like that correspond to dirt on the CCD
> window of my camera.

OK, as per your suggestion and Stan Truitt's I will try tilting the
camera and see what happens.

Richard Ozer wrote:
> I'm curious about the 6" machine generated mirror that looked like
> a bullseye.  You mentioned that it tested to 1/8 wave.  What test 
> concluded that and was that PV or RMS in the calculations.

Richard,

We did a Foucault test with a reasonable number of zones, and FigureXP 
showed a P-V wavefront error of ~1/4 wave, so that's ~1/8th wave on 
the surface.  Due to all the zones the Foucault test could have been 
off a bit (assumption of a smooth surface is kind of a bad one on this 
mirror), but we were just getting an idea of the form of the surface. 
  The error plot did show some of the zones.

All,

More photos (Foucault and Ronchi) of a horribly astigmatic mirror 
coming soon - you don't want to miss it!!!

	Mike L.

_______________________________________________
ATM mailing list http://www.atmlist.net/