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    Re: Sextant and Eye Optics
    From: Bill B
    Date: 2006 Dec 06, 03:57 -0500

    Michael wrote
    
    > Then you take the sextant out in the dark when the
    > eye's focusing mechanism doesn't always have enough
    > power in the image to operate properly.  Those of us
    > who use spectacles can test this by going out in the
    > middle of a dark night ( moon perhaps too full at the
    > moment ), wait for your eyes to adjust, then look at
    > the stars ( no instrument ) with and without the
    > specs. You will find that the specs don't make any
    > difference at all....
    
    For me (for many reasons) I believe dark adapting is a poor choice for cel
    nav in most cases.
    
    If you have been reading the list for awhile, Frank Reed pointed us to an
    article in the September 2205 "Sky & Telescope."  It was titled, "Optimizing
    Your Eyes for Astronomy." It dealt with night vision--among other
    topics--and adjusting an eyeglass prescription for night viewing. At the
    risk of again hitting the same nail with the same hammer (which is not even
    mine), I again recommend the article.
    
    Bill
    
    
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