[ATM] getting the foucault test right

["David Williams" <dwilliams1128@earthlink.net>]

Hello ATM list

I have the foucault tester and the 20", 1" thick mirror, uncoated, and I think that it is hyperbolic.  And right now I'm wondering how to take pictures of the shadowgram so that I can show you guys what it looks like so that I can get your advice on what to do next.

I have a Bronica S2 medium format camera and that would have good resolution because of the finer grain, but the ground glass makes it harder to focus the image.  Then I have a Pentax K1000 camera (that is 35mm).  Then there is a camcorder that takes not only video, but still pictures.  The problem with all of these is that the foucault test is so sensitive that I barely move and the image is off.  And I have the camera mounted on a tripod, but that doesn't help either.  

Maybe the door was in the way and I should move the mirror to the left so that I can get enough clearance with the tripod on the right.  

PS What does anyone think about the couder mask that I made, here it is:

http://www.atmlist.net/contrib/dwilliams1128-at-earthlink-dot-net/20%22Telescope%20Stuff/CouderMask20Inch.jpg

Thanks 
Bye.
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