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    Re: Simplified Bris Sextant (calibration)
    From: Greg Rudzinski
    Date: 2012 May 15, 12:21 -0700

    Bill,
    >"Are two crossed polarizing filters (with on other filters) dark enough
    to view the sun with the naked eye?"

    Yes they are dark. Not quite as dark as astronomy solar film.

    You should see a comfortable blue disk with the polarizers filtering the maximum. You can't just stack two polarizers. It is necessary to take one of the polarizers out of the frame and reverse it over then install back into the frame. Test by flipping one of the polarizers 180* relative to the other while off the lens.

    Greg
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