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    Re: Proportional logs, etc.
    From: Henry Halboth
    Date: 2004 Aug 27, 00:03 -0400

    AH - sooo. Many thanks again, this time to Bruce and Frank, on the
    calculation of prologs. I was slowly coming around to the conclusion so
    well stated in your postings, but simply could not find support stated in
    any written form. Unfortunately, I am still not proving out Brother
    Arnold's tables for Sun and Star corrections, but will keep plugging away
    at it.
    Per Jan's posting, I assume that one could possibly construct a prolog
    table for another interval, i.e., 60 minutes, 120 minutes, etc., and
    confuse the hell out of the opposition - almost like a code.
    On Thu, 26 Aug 2004 19:39:13 EDT Bruce Stark  writes:
    > Henry,
    > As for how to calculate proportioning logs:
    > They are for a three hour interval, and designed to proportion to
    > the nearest
    > second of time. Three hours contains 10800 seconds.
    > One hour contains 3600 seconds. So the PL of one hour is simply the
    > log of
    > 10800/360.
    > The PL of seven seconds is the log of 10800/7.
    > The PL of one minute, six seconds is the log of10800/66.
    > And so on.
    > Since there are 10800 seconds of arc in three degrees, PL tables can
    > be used
    > to proportion small angles as well.
    > Hope this helps.
    > Bruce

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