From: "Bob May" 
To: "atmlist" 
Reply-To: "Bob May" 


The test as being done by the RoboFoucault tester flipping the image and
doing the difference process is essentially the same as the wire test (not
the caustic test) as the wire is basically doing two Foucault tests at the
seme time - one with the KE to the left of the light and a second with the
KE to the right of the light source.  What ends up is that the alignment of
the widths of the source and wire produce an image where the general part
of the surface is bright but there is a band at the ROC of that zone where
there is a dark band where the light is blocked from either side of the
wire.  The computerized difference operation is a bit more sensitive in
this regard for contrast but the same basic result is obtained. Bob May
http://nav.to/bobmay
bobmay{at}nethere.com
NEW! http://bobmay.astronomy.net

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