Yep,
It seems to be a GRAT--generally recognized as true. I have read this
and I think observed this. Why should it be the case that a linear
pol would have a greater effect when the circ pol just has a quarter
wave retarder added? The extinction coefficients of the pol material
vary by wavelength as shown in the test---less efficient in the blue
area thus a cooling effect. The mistaken linear pol (?really a linear
pol mislabeled or the quarter wave retarder had the wrong orientation?)
had some of the highest ext coeff scores but some of the others did
indeed match it. Perhaps adding the extra element necessarily lead to
further reduction in light transmission so they keep the ext coeff
lower in general for the average circ pol to prevent too much light
loss---I don't think so. Another factor is the quarter wave retarder
also has differential effects by wavelength---It tends to WARM the
image back up!
Perhaps not quite a "Moose filter."
http://www.clarkvision.com/photoinfo/evaluating_polarizing_filters/
So part of the less perceived pol effect with the circ pol could be
the reduced cooling effect on color balance.
Total speculation, I could be all wet.
Perhaps Idle thoughts of an addled mind,
Mike
Where is Dr. Polarizer hiding?
> I think he is referring to the fact that the "accidental" testing of a
> linear polarizer gave far the best test results.
Nope. I've always felt that the linears I had provided a much deeper and
intense polarization effect.
AG
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