How I built the 12 inch scope
Foucault & Ronchi tests (Part 2)

This is the next session of pictures. Again in this picture I am right on the focal length using a knife-edge test. I have managed to remove the center hill, a little to far though.

The line seems a little wavy, but the Rouchi screen is woven mesh. This makes it difficult to get it perfect. I have been told that spider web is the best stuff to use.
This is what it is meant to look like.
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