Good morning all:
One of the things that should be included on new RCs (GSOs, etc.) are collimating flanges for the focuser/mirror assembly. Of course, this is just wishful thinking on my part. That being said, try finding one new in CONUS. However, I did find some available at Telescope Service in Germany and placed an order. It would seem that Telescope Service is highly regarded and this is my first transaction with them.
Also, one of my questions is the extreme backfocus required. Then I got to thinking....to get shorter back focus, the secondary would have to curved more strongly or be larger, increasing the already large central obstruction. Am I on the right track for understanding how this optical design works?
Edited by hypergolic, 27 January 2021 - 09:48 AM.