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Re: Definition Sight Reduction Tables
From: Robert VanderPol II
Date: 2017 Mar 17, 13:37 -0700
From: Robert VanderPol II
Date: 2017 Mar 17, 13:37 -0700
The way I see it there are 2 basic definitions with some gray area in between.
A] Sight reduction is processing all of the data from the sextant and watch until you plot a line or lines. This include references to the almanac as well as sight reductions tables. Plotting may or may not be included. I don't think the shooting of the celestial bodies is normally included. You may choose to start the definition of after correcting the watch time and Hs.
B] You may choose to just define it as just the parts that involve the sight reductions tables, that is entering with GHA, DEC and an AP or EP to get Hc and Azimuth.
I think the phrase is generally used as in A].
I know what they are and can use them but if someone asked me to give a definition of the term sight reduction I would be beat. Cannot help thinking it is to do with bringing the GP's of the HB's close to our DR therefore making a reduction of the size of the chart required to make a plot. From about a mile square to the size of a plotting sheet.
