Linear pola vs. Circular pola

Discussion in 'Miscellaneous Equipment' started by jsimoespedro, Jan 21, 2013.

  1. jsimoespedro

    jsimoespedro Member

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    Hi all,

    What is the practical difference between a linear polarizer and a circular polarizer?

    Thanks.

    Joao
     
  2. chriscrawfordphoto

    chriscrawfordphoto Subscriber

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    Some SLR cameras has semi-transparent mirrors to allow some light to pass through them to autofocus sensors or light metering cells under the mirror. If you have such a camera, you need a circular polarizer because a linear polarizer causes inaccurate meter readings and interferes with autofocus.

    All AF 35mm SLRs are like this. Several manual-focus cameras are too, like the Nikon F3, Olympus OM-4/4T, OM-3/3Ti, OM-PC, and OM-2sp
     
  3. AgX

    AgX Member

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  4. jochen

    jochen Member

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    The Nikon F-3 does not need circular polarizers as the camera has no semi-transparent mirror but many very very small slits in the center of the mirror.