Foucault and Ronchi
tester with mirror stand
Ross Sackett's amateur telescope making
My telescopes and ATM Projects
The tester is mounted on an X-Y
stage intended for a drill press,
available from MicroMark.  It has a
knife edge on one side, and an 85
LPI Ronchi screen on the other.  
Both are fed by white LEDs.

The tester is made mostly of baltic
birch plywood, with a mahogany
combination stain-poly.  The tester
is mounted on a granite tile for
stability, with three vinyl feet.

The mirror stand is made of MDF
with the same finish.  There is black
velvet behind the test mirror for
improved contrast.