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Re: Path of light...



The helical description sounds circularly polarized waves.
This bring another question to mind. Anyone know why you are supposed
to use circular polarizers rather than linear polarizers on automatic
cameras. I think this is principally for autofocus SLR's. I find
that even with circular polarizers the meter consistantly underexposes
and find no real benefit to circular over linear (except that somebody
made a lot more money selling me the circular polarizers).

Howdy,

Many SLR's "read" light reflected from the mirror of the ground glass
image. Because of the reflection off the mirror (which doesn't reflect
linear polorized light with E-fields perpendicular to the surface of the
mirror as much as those with parallel E-fields) you can get an improper
exposure reading.

Good Luck,

Herb Schulz
(herbs@interaccess.com)