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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: A basic sight reduction question
From: Gary LaPook
Date: 2012 Apr 4, 09:44 -0700
From: Gary LaPook
Date: 2012 Apr 4, 09:44 -0700
I never noticed the situation that you pointed out. The answer is that the "v" and "d" correction tables in the N.A. are simply multiplication tables, multiplying the "v" and "d" factors (which are simply how much the body changes its position in one hour) by the proportion it will change in a period less than a full hour. Since the tables only list correction for whole minutes they are actually the average correction for the whole minute tabulation so they are actually calculated for m + 30 seconds. They can be considered precise only for the +30 sec case and approximate for other times. If you wanted more precision then just divide the "v" or "d" by 3600 and multiply by the number of seconds after "on the hour." If you do it this way then you will find the correction for "on the hour" is zero, zero seconds times any "v" or "d" value will always equal
zero. But you are trying to make it too hard on yourself. gl --- On Wed, 4/4/12, slk1000@aol.com <slk1000@aol.com> wrote:
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