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Re: Proportional logs, etc.
From: Henry Halboth
Date: 2004 Aug 27, 00:03 -0400
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. Regards. Henry On Thu, 26 Aug 2004 19:39:13 EDT Bruce Starkwrites: > 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