polarizer?

[WR <rivelli@xxxxxxxxxxxxxxxxxxx>]

Yes, a Polarizer in combination with a red [such as a #25] filter 
works very well indeed. I have taken some spectacular photos on clear 
"ideal IR" days.

The filter factor is pretty easy to figure out too; in my case,
1 1/2 stops for the Polarizer plus 1 1/3 stops for the #25 with Kodak 4x5 or
  1 1/2 stops for the Polarizer plus 2 stops for the #25 with Konica 120.

These filter factors are a result of tests I did long ago and still 
work. I only bracket +/- 1/2 stop, and often not at all.

Other filters will work too, to different degrees, depending on how 
much of the visible spectrum you are cutting off. You must EXPERIMENT 
to find out what works for you!!  Use a few sheets and keep good 
notes.

Good luck...

       William Rivelli
WILLIAM RIVELLI PHOTOGRAPHY

rivelli@xxxxxxxxxxxxxxxxxxx
     www.rivelli-william.com
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