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Thread: Polarizers

  1. #1
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    Polarizers

    Just a quick and simple question. What's the difference between circular and linear polarizers on the effect of the resulting image? From what I gather the only real difference is that modern cameras meter through circular polarizers better then they do through linear polarizers, but that the actual effect on the image is the same(given proper exposure, of course). Is this correct? Thanks.

  2. #2
    Sitting in a Leaky Dingy Michael Fanelli's Avatar
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    Quote Originally Posted by PerPlunk
    Just a quick and simple question. What's the difference between circular and linear polarizers on the effect of the resulting image? From what I gather the only real difference is that modern cameras meter through circular polarizers better then they do through linear polarizers, but that the actual effect on the image is the same(given proper exposure, of course). Is this correct? Thanks.
    A linear polarizer polarizes light in an "up-down right-left" manner. This interferes with the beam splitter that assumes the light is unpolarized. A circular polarizer adds a 1/4 wave retarder plate to the back of a linear polarizer. This "twists" the light so the polarization is now more of a spiral (not really circular). The beam splitter is not adversly affected by this type of polarization.

    Yes, you get the same effect with either one.
    "Every great decision creates ripples--like a huge boulder dropped in a lake. The ripples merge and rebound off the banks in unforseeable ways.

  3. #3
    has-been... another view's Avatar
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    You've got it right. AF cameras need circular polarizers. Actually since good polarizers are expensive, I'd only buy a circular - you probably need it at some point even if not today.

    The effect is the same on the image.

  4. #4
    nature/wildlife co-moderator paulnj's Avatar
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    WOW Mike.... I now know how a circular polorizer is made and technicly works

    THANK YOU , as I only knew which one is needed, and how they basicly work .
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