Re: ATM 6" mirror

[Michael Coslo <mjc5@psu.edu>]

        Here are a few things to try:


        Check the manner in which you mount the primary and secondary 
mirrors. If you use clips, are they binding on either of the mirrors? 
Especially check the secondary, lots of bad mirrors are actually 
poorly mounted secondaries.

        Try rotating the primary if you can. If the astigmatism 
changes directions when you rotate it, it is the primary, if not, 
look elsewhere.

        I'd be willing to bet a cup of coffee that your problem is in 
the mounting system, and that is good news, because you can do 
something about it.

        - Mike -

At 1:27 PM -0400 8/8/00, Viper71049@aol.com wrote:
>
>awseome.  Then I turned it to a star, Antares(0.92mag), and saw the image as
>a stretched star.  I then figured I had astigmatism.  I don't want to try to
>re-polish because I am out of pitch and Cerium Oxide so I am thinking of
>either finding or making a corrector lens for astigmatism.  Is there anyone
>who can help with me on this or is there any other thing that can fix
>astigmatism.  I believe the astigmatism in my mirror was cause because I did
>uneven stroking.
>Tony