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    Re: Precision of lunars
    From: Frank Reed
    Date: 2007 Apr 25, 23:28 -0400

    Alex, you wrote:
    "Can you cite or post ANY data or statistics"
    
    uh... sure!
    
    With a good, well-adjusted sextant, I get a standard deviation for Moon-Sun
    lunars, and of 0.2 minutes of arc on individual sites. On sets of four,
    averaged, I get an s.d. of 0.1 minutes of arc. For Moon+other object
    brighter than magnitude 0.5, I get similar results. With fainter stars, the
    results are progressively worse (bear in mind that something like 80-90% of
    the historical lunars I've seen in logbooks are Sun-Moon lunars). These
    results haven't changed in years for me, but it all depends on the sextant.
    It has to be an instrument that has been well-adjusted, tested for arc
    error, made of metal (no plastic sextants for lunars!), and carrying a
    telescope with a magnification of 7x or better. Now, if you want to see data
    for individual sights, I posted many series during the 3.4 years I've been
    on the list. You can search the archive if you want: www.fer3.com/arc
    
     -FER
    
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