5 ms·

Story of Palomar - 1948 https://m.youtube.com/watch?v=4miVqgNSRVY https://m.youtube.com/watch?v=4miVqgNSRVY

• DrFell 4y ago
  At about the 20 minute mark, they show the Foucault testing of the mirror, and actually put a camera at the test focus, so you can see a Foucaugram of the mirror. It's of poor quality, but still. You see the donut. To anyone who was into amateur telescope making, ground their own mirror, used the Foucault test, and was as interested in mirror metrology tests as I used to be, this is absolutely fascinating. https://www.youtube.com/watch?v=4miVqgNSRVY&t=1223s https://www.youtube.com/watch?v=4miVqgNSRVY&t=1223s