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    Re: HO 211 Sadler Technique
    From: Paul Hirose
    Date: 2014 Mar 09, 13:45 -0700

    "Compact Sight Reduction Table" by Allan E. Bayless, a modified HO 211,
    shows the Sadler technique with this example:
    
    89° 06′ t                 B 180390   A     5
    53° 16′ S dec   A  9614  +B  22323  +B 22323
    33° 19′ S lat  +A 26022  +B   7798
                       -----
    26° 07′ h1      A 35636
    26° 35′ Ho
    -------
    52° 42′ h1+Ho
    26° 21′ (h1+Ho)/2        -B   4764
                                 ------
      0° 30′ h2                A 205747
    -------
    26° 37′ hc = h1+h2                  -B  4865
                                            -----
    41° 59′ Z                            A 17463
    
    
    With a calculator I get Hc = 26° 37.1′ and Z = 41° 59.0′.
    
    Speaking of the Bayless table itself, I don't like it as well as the
    Ageton table in Bowditch vol. 2. (I don't own a "real Ageton".) To cut
    the table size in half, Bayless goes up to 45° instead of "turning
    around" at 90°. This is possible because of the symmetry of the trig
    functions, e.g., sin 80° = cos 10°. Thus the table need only go as high
    as 45°. However, it requires a double heading at the top and bottom of
    each column. Depending on the angle, the left hand column can be either
    the A or B value of the angle.
    
    On the other hand, the table in Bowditch always has the A value on the
    left and B on the right. In addition, the B column is boldface. These
    things help you avoid blunders.
    
    The other thing I don't like about Bayless is that he omits the leading
    digits when they are the same for several consecutive entries. For example,
    
    33925
       901
       876
       852
       827
    
    so you have look in two places to get all the digits.
    
    --
    
    

       
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