Astimatic Secondary

RicH2@aol.com
Sat, 8 Jul 1995 01:38:04 -0400

The beauty of a dual mode telescope such as my Parks 10" HIT Cassegrain/Newtonian is that when you have an astimatism in one mode you can change out the secondary and see if the problem is in the primary or not....... It's not. My newtonian secondary (the one with the astimatism) came with chunks of foam stuffed in behind it to hold it in place in it's holder. Any ideas on how to assure even preasure across the surface of the mirror? Moving the foam around has only changed the astimatism but not gotten rid of it. Is this a hit and miss adventure or is there some other method for securing the mirror? This would not be the first thing I found a better way to do over the manufacturer if there is one. Thanks in advance for any help or ideas.