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    Re: sight reduction tables
    From: Peter Fogg
    Date: 2007 Oct 6, 05:38 +1000
    I think you're quite right (hardly wrong at all !) with those perceptive comments about how the HOs remain popular.

     Lu wrote:


    You're both right and wrong (no personal insult intended).  There
    certainly are many ways of doing sight reductions and even today people
    are inventing new ways to do it.  

    One trend I've noticed here is newcomers, fairly quickly after understanding the process, setting up their own spreadsheets to handle sight reduction. While its reinventing the wheel, I'm sure it leads to a very good understanding of the process.

    Ageton (HO 211) is a result of someone
    skilled enough in math to say "there's a different/better way to reduce
    sights" (where "better" in Ageton's case meant "simpler, more compact
    tables even at the expense of more steps").  HO 229 resulted from
    computers becoming commonplace enough in the 1950s to allow vastly
    larger and more accurate sight reduction tables to be calculated.  And,
    of course, the solar-powered $15 pocket scientific calculator has made
    all tabular methods obsolete, at least in some people's opinion.

    And the current edition of the book that contains the simple, easy to use sight reduction tables also has a page of useful formulas for, among other purposes, sight reduction.

    But the issue extends beyond that to things like training.  All of us
    have learned to reduce sights either by reading a book or taking a
    class.  That class or book trained us in one particular sight reduction
    method.  Sociology tells us that people will not change a way of doing
    things unless they perceive some significant reward as a result of
    changing.  How many celestial navigators will want to learn a new method
    just because it might be "better" than the method they originally
    learned?  You might, I might, because we're curious about the whole art
    of navigation.  But would the average offshore voyager?  Or will he/she
    stick with sun sights and HO 249?

    Hand in glove with training is availability.  If I'm preparing for an
    offshore voyage and I want a set of celestial navigation tools, I'll
    probably go to a large and expert supplier such as Celestaire or
    Landfall.  What sight reduction method I use is going to be limited by
    what's in their catalog.  Again, some experts may seek out new and
    different ways of doing it, but for many it's "what's in the catalog."

    Celestaire was a retailer, for a period, of an earlier edition of 
    The Complete On-Board Celestial Navigator. 
    Although that is 'by the way'; the general point you make is quite valid.

    So, yes, you're right that there are many ways of reducing sights.  But
    as many people in the past who perceived a "better way to do it" have
    learned, what gets sold and used is determined much more by
    non-technical factors such as commonplaceness than simply by technical

    I guess..

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