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    Re: Sextants with Polarizing filters
    From: Frank Reed CT
    Date: 2006 Feb 6, 18:12 EST

    Joel Jacobs, you wrote:
    "MAYBE THE BIG  BUGABOO IS THAT WHEN SUBJECTED TO SALT SPRAY THEY TENDED TO
    FREEZE AND ALSO  FROZE IN FEARCELY COLD CONDITIONS.. AND INTRODUCED ABOVE
    AVERAGE SHADE ERROR  OVERALL."
    
    Regarding salt spray and freezing, I think you've hit the nail  on the head.
    I have noticed that they stick hard in cold weather. I suspect that
    polarizing filters seemed like a nice "high tech" innovation 60 years ago, but  in
    practice easy maintenance won the day.
    
    As for shade error, I can't  think of any reason why polarizing shades should
    have greater error in general.  And since the elements rotate, if there
    really was greater shade error, it would  also be variable!
    
    -FER
    42.0N 87.7W, or 41.4N  72.1W.
    www.HistoricalAtlas.com/lunars
    
    
    

       
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