Re: ATM Re: Edmund Scientific's 4.25 mirror

["Charles Hovatter" <charleshovatter@acelink.net>]

JP wrote:

>I was just looking at those mirrors in the Ed Sci catalogue
>a couple of days ago. It appears to me that, if the graph of
>reflectance as a function of wavelength is correct, then the
>enhanced
>coating would perform significantly better in the visible
>wavelengths and so would be worth the extra $36.
>
>Are Edmund's prices competitive?

Better get the standard aluminum.   I have heard some really bad things about
the enhanced coatings as of late.  Light scatter, and figure changes (on large
mirrors).   Go to Deja News and do a search of sci.astro.amateur for "enhanced"
or something like that.   See what you think.   Not believing everything I read
on NG's, I e-mailed a coating firm in Florida.   The do them, but they do not
recommend them!   They said standard is better.
-Chuck