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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

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    Polarising Filters
    From: Clive Sutherland
    Date: 2007 Nov 22, 18:42 -0000
    Hi all,
    In view of the recent interest in these filters  I have extracted a reference article to help those who are unfamiliar with using polaroid. It was written by an highly regarded astronomer but I have edited it to make it more suitable for the NavList. It is quite an old article and does not have any references to Nematic materials but useful nontheless. I am sending it as a WORD 2003.doc attachment so that I can include a chart.If anyone is unable to read it come back to me and I will send something else off-list   
    There is an good idea lurking here! How about,  for a 21 cent Sextant, using a Liquid crystal filter in front of the sextant telescope fed from a hand-held so as to produce an opaque 'Sun' or 'Moon'  or 'bright sea'  just where it is needed to block off the dazzle. I don't think anyone has yet thought of that!

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    File: 104012.polarisation.doc
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