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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Traditional navigation by slide rule
From: John Brown
Date: 2016 Jan 20, 03:40 -0800
From: John Brown
Date: 2016 Jan 20, 03:40 -0800
Bob wrote:
Podmore's trig scales are set up for degrees and minutes. Having used those now, I am less convinced that they are better than decimal degrees. The increments sometimes represent 30', sometimes 20', and sometimes 5', sometimes 2', 1', or 1/2'. A guy has got to think about his audience here... and I think people shift gears mentally to different increments easier in decimal degrees than degrees and minutes.
I am with Bob on this, given the attainable precision on a ten inch slide rule. We don't seem to have a problem with the decimalisation of seconds of arc and mental interpolation.
BTW, my C Plath sextant has no vernier on the micrometer screw. I find it uncluttered and very easy to estimate the tenths.
John
