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    Re: Sextants with Polarizing filters
    From: Ken Muldrew
    Date: 2006 Jan 25, 20:02 -0700

    From:                   Bill 
    
    > George
    >
    > Sorry you do not endorse my paraphrase ;-) Googled filters today, and
    > a maker of fine optics, Schneider, used the same analogy (albeit a
    > better explanation--a picket fence:
    
    Bill,
    If you have 3 polarizers you can easily see how the picket fence analogy
    fails. Simply line up 2 filters with a space between them. Rotate one until you
    get maximum darkening (here the axes of polarization are at 90? to each
    other). Now insert the 3rd polarizer in between the other two. Suddenly light
    passes through all three! How could the middle polarizer change the
    orientation of the other two "picket fences"?
    
    Ken Muldrew.
    
    
    

       
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