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    Re: problems with artifical horizons
    From: Alexandre Eremenko
    Date: 2012 Mar 20, 22:02 -0400

    Alan,
    
    1. As you already measured the alt of the sun before,
    you could preset your sextant on this altitude.
    Pre-setting sextant on an approximate alt frequently helps, espesially
    if you observe through the holes in the clouds, and have little time
    to search the sun.
    The approximate alt can be computed with
    a) star globe, if you have one (Russian manuals recommend this)
    b) a star finder (there are many types, soe of them cheap and handy).
    c) special tables (the Complete on board Celestial Navigator has them).
    In general, tis is an excellent thing, don't know why they do not cell
    paper copy anymore. But you can print and bound yourself).
    
    2. I also use the following method sometimes. With real or artificial
    horizon,
    especially with stars.
    Take your sextant upside down, point it on the Sun, so that you see it
    through your horizon mirror (don't forget the shade). This is easy,
    becasuse you feel where the Sun
    is with your face. Then swing the arc to catch the reflected Sun.
    Once you catch it, take the sextant in the normal way.
    
    This is easier with Davis if you put its own filter on it,
    and remove the sextan Index filter from the field of view, while
    searching. Don't forget to put it back when you invert the sextant to hold
    it in the normal way.
    
    3. Another method. Remove the telescope. This helps in searching.
    Especialy if your telescope is a strong one with a small field of view.
    Once you catch the Sun, put  the telescope back.
    
    Hope some of these techniques help.
    
    Alex.
    
    
    
    
    

       
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