Re: Aluminium and reflectivity
SCHRAMMR@WLSVAX.WVNET.EDU
Sat, 27 Jul 1996 18:52:19 -0400 (EDT)
An alloy of berrylium and aluminium is used to coat telescope mirrors, but
when they want the best possible coating, silver is used since it has the
largest albido of any known substance (i.e. ratio of reflected light to
incident light). The mirrors are then quartz overcoated to prevent oxidation.
I think the crinkled aluminum foil generated lots of little hot spots which
acted like a bank of point sources which resulted in multiple imaging on
the print.
Bob Schramm