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Very Good But.

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Posted by Rick Crockett on February 9, 2001 03:44:52 UTC

All my sources put silver at a maximum of 92-93% for visual green and less for the PV spectrum.

I know of a 99% silver alloy coating but that requires 40+ dialectric coatings.

My Perkins and Elmer and everyone I have used referenced the reflection reading against a black body box. The machine was calibrated using targets for example coated with TiO2. I don't believe it would accurately measure reflectance of a mirrored surface. Does your model provide for interceptance of a measured beam or does it calibrate against other targets?

It just sounds too simple but hey even if you get a protected 92% PV silver coating, that is pretty good. Thanks Al. I silvered my 22" by chemical process and it worked beautifully. Unfortunately, in smoggy S. Cal. and downwind of a high sulphur oil burning power plant the silver is only good for two nights. Varnish is not very good for protecting a mirror that size.


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