The Optical Test Bench

What good is grinding a mirror if you can't somehow verify that it's the right shape? This test bench is a key element to the workshop. It allows people to run either the traditional knife edge test or the Ronchi test using either the Center of Curvature or Autocollimation techniques. People can check their progress along the way and validate the finished product.

(left) The bench is setup for the traditional knife edge test using the Center of Curvature technique. Behind the light source is the video camera which sends the results to either a VCR and/or a monitor. The mirror under test gets mounted on a sliding carraige designed to allow for various focal lengths.

(right) We can attach a 16 inch perforated flat for the auto- collimation technique. It's mounted in a box that's clamped to a yoke which controls mirror tilt. The light source, knife edge holder and slides are under the yoke. With this test, there is no data to tabulate or data reduction analysis needed.

The Class Room

I call it that only because I don't know what else to call it. I've taken a corner of the basement and setup some comfortable couches and a TV. Here, people can sit down and absorb instructional video about mirror-making technique, optical theory, or whatever else we have to help accomplish the task at hand.

Show-and-Tell

Where to go next? One year, we laid out this table which had the information you need to complete the rest of your telescope after the mirror is finished. (Everything needed for this OTA was home made.) Though this table was only out one year, we typically have some form of Show-and-Tell to provide ideas and options for taking the next step toward completing your telescope.