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    HO 211 / Bayless
    From: Paul Hirose
    Date: 1999 Sep 06, 3:28 PM

    Russell and the group -
    For use at home I prefer the Ageton Method table in Bowditch over
    Bayless.  The Bayless book is a paperback so it flips shut when you
    take your hand off it.  Another annoyance is that leading digits are
    omitted when they are the same for several entries in a row.  Compare
    Bayless to Bowditch:
     Bayless     Bowditch
     50042       50042
       004       50004
     49966       49966
       928       49928
       890       49890
    I find the Bowditch format can be read with more speed and certainty.
    The Bayless rules for negative Hc are incorrect.
    Finally, the table in Bowditch always has the A value in the left-hand
    column and B on the right.  In addition, all numbers in the A column
    are boldface.  The consistent layout lowers my mental workload
    noticeably, and is the biggest advantage of the older table.  I need
    all the help I can get!
    Bayless chose to take advantage of symmetry (A of 10 deg. = B of 80
    deg.) by making each column do double duty.  This clever trick cut the
    table size in half, but also made it unavoidable that the A and B
    columns would periodically swap positions.
    There are pluses to the Bayless table.  The book measures only 9" x 6"
    x 1/8".  I find the table pleasantly clean in appearance, without all
    the unnecessary dividing lines seen in Bowditch.  Bayless includes
    D.H. Sadler's method for reducing sights with full accuracy when LHA
    is in the Ageton "danger zone" near 90 or 270.  Also included is
    Elliot Laidlaw's graph for determining your proximity to the danger
    zone (it's a function of t and dec).  Neither of these is available in
    If I were doing celestial at sea instead of at a desk, I'd probably
    prefer Bayless for its cheapness, compactness, and robustness (the
    paper is heavier than that in Bowditch).  Original HO 211s are
    practically a collector's item nowadays.  If I owned one I'd be
    reluctant risk getting it wet.
    My comparison may be a bunch of moot points.  I'm not sure if the
    current Bowditch has Ageton's table.
    Another variant on Ageton's method is Mike Pepperday's S-Table.  I
    think Celestaire still sells it.  Pepperday has an improvement over
    both Ageton and Bayless:  the table goes all the way to 360 degrees.
    That means you enter it directly with LHA, instead of having to
    compute t.  The extended range is accomplished with additional column
    headings; the table is no larger than Bayless.  (Of course you can
    annotate your Ageton table with a pencil to extend its range - that's
    what I'm doing.)  I don't know if Pepperday includes the Sadler and
    Laidlaw info.

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