Don Simanek asks what the advantage of circular vs linear polarizers was
supposed to be for cameras. The claim is that the circular polarizers
so not mess up the light meters and focusing mechanisms. The suggestion
that these devices use reflected light seems like a good one. However,
my experience is that even linear polarizers do not interfere with auto
focus (Nikon 8008 and 8008s) and that even circular polarizers do result
in underexposed images. Anybody else have any experiences to add?