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    Lunars hard to shoot
    From: Richard B. Emerson
    Date: 2000 Sep 13, 6:29 AM

    Paul Hirose writes:
    [...]
     > It was a little surprising to see Carl Herzog's statement that the
     > choice of whether to use the horizon glass or index mirror for the
     > Moon is mainly a question of physical convenience for the navigator.
     > I'd expect the index shades to be much darker, since they have to
     > make the direct rays of the Sun safe to view. (Remember, I own a
     > bubble sextant but no marine sextant.)
    [...]
    
    Both my Plath and Astra have filters ranging from dark enough to shoot
    the Sun to just enough to dim a partial Moon.  Since a common
    technique for starting a run of sights involves looking at the body
    with the index set to 0-0.0 and "dropping" the image, both the index
    and horizon filters should allow seeing anything from the Sun at high
    noon to a dimmer star like Polaris.
    
    Remember, too, that filters can be used in combination, offering an
    even wider range of intermediate shading.  The Astra also has a green
    filter which can be used to make the Sun or Moon stand out a bit from
    what's seen on the horizon.  There are times when I wish I had the
    same option with the Plath.
    
    Rick
    S/V One With The Wind, Baba 35
    

       
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