How I built the 12 inch scope
Foucault & Ronchi tests (Part 1)

I managed to get some pictures of my tests. These pictures were taken after 3 hours of polishing. In this picture I am right on the focal length using a knife-edge test. As you can see there is a central hill.
Now we are looking through the Rouchi screen. I took all my tests inside the focal length. This picture is of a moderate zoom.
Again through the Rouchi screen, zoomed further. As you may notice the camera is a little (mm or so) to the left of were it should be to be square on.
I have zoomed a bit further but this is really ineffective as we are zooming in on the center of the mirror. You can clearly see the small hill. To remove this hill it only took 10 minutes of little movements with the polishing tool over the center.
This is what it is ment to look like.
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