Re: [ATM] Silvering Mirrors

[Dominic-Luc Webb <dlwebb@canit.se>]

Interesting! I guess the bronze hue might be problematic for
photometric measurements or for observing objects with colored
patterns of similar color, etc. As an afterthought, I wonder
if you can get silvering that is partially, like 50%, reflective
so you end up with a beamsplitter? That could be kind of cute in
an optical tester, or maybe just to split an image between two
detectors. Beamsplitters are generally rather expensive. I can
imagine a few applications where this bronze hue would not
matter.

Dominic



On Fri, 25 Jan 2008, Bill Kelley wrote:

> Sorry Dominic-
> So much had been written about tarnish protection that I neglected to
> mention that many of the mirrors have caps that fit snugly over the mirrors
> and have a little piece of anti-tarnish cloth in the caps. We live and
> observe in a rural part of Arizona more free of sulphur than most places.
> One unprotected scope after two years has a bronze hue but the images seem
> just as bright and the bronze hue is only a bit noticeable on the moon. I
> seem to recall seeing a scope made by a member of this list with a very
> deeply tarnished mirror- but the images were brighter than you would think.
> I'm afraid that I gave the impression that silvering was for everyone. Bad
> me- not so.  However,the writers who flamed the idea do silvering a
> disservice.

_______________________________________________
ATM mailing list http://www.atmlist.net/