Ed "You have to grow old, you don't have to grow up."
Quote:It seems that no matter what kind of alterations you enter, or a number of them, the system can be brought back to correction, often simply by no more than respacing the mirrors. Mladen
Quote:OK - secondary radius tolerancing done, with results you will like. First, the prescription and tolerance table.
The low secondary amplification and resulting long ROC is indeed the reason for the loose radius tolerance. The limiting case is, of course, a flat secondary mirror!
Notice the asymmetry of the WFE curves going from too steep to too flat. They suggest that it is slightly better to err from nominal toward a longer rather than shorter radius, if you can stand the shorter system EFL.
Notice also that I pulled your foldout tertiary mirror away from your secondary by 3", reducing the path to focus from 28" to 25". I don't know if you were aware of it, but your tertiary was blocking a large lune of light headed from the lower side of the primary to the secondary.