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    Re: Sextant Telescopes
    From: Rodney Myrvaagnes
    Date: 2004 Mar 28, 22:23 -0500

    On Sun, 28 Mar 2004 07:42:50 -0500, Joel Jacobs wrote:
    
    >
    >A 4 x 40 is considered a STAR Scope because it transmits more light through
    >the optics than higher powered scopes. Its wider field of vision is an
    >advantage in low light conditions.
    >
    It isn't so much the field of view as the f/stop (in camera speak) that
    makes the 40 mm objective better than a 30. The 7X50, if the optics are
    good, makes a great twilight glass for lloking into an anchorage when
    you can't se in the shadows with the naked eye. The same quality would
    help gather light from a star.
    
    I have a question. has anyone adapted an image-stabilized glass to a
    sextant? A few weeks birding with a Canon 6X30 IS binocular suggests it
    (one barrel of it) would be usable on a small craft, which an
    unstabilized 6X30 really is not in any wave action.
    
    I am sure you can't just saw it in two, because the motion sensor is
    certainly shared. Given the small market for sextants, I suppose it is
    unlikely any of the optics companies will make a sextant scope in the
    future with this feature.
    
    
    
    Rodney Myrvaagnes     NYC                                               J36 Gjo/a
    
    
    "Accordions don't play 'Lady of Spain.' People play 'Lady of Spain."
    
    
    

       
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