Re: ATM Re:Moon and Polarizing filters (shortish)

[Spencer Roedder <roedder@roedder.com>]

At 04:43 PM 98/07/11 +0800, Clive wrote:
>
>    The figure of 35% or 45% seems to ring a bell, and 9% if two are stacked
>90 degrees out of phase......( that is theoretically perfect polarisers )

I would believe 35-45% for a single polarizer, or two in parallel - but I
am sure that even real life polarizers at 90 degrees get a lot better than
9%.  My guess is something in the 1% range.  I know I have seen them get a
lot darker than "aviator" sunglasses, which are about 10% transmission.

--Spencer Roedder   roedder@roedder.com