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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Significance of azimuth errors, was : Principles and Being Practical
From: Trevor Kenchington
Date: 2003 Sep 7, 23:01 -0300
From: Trevor Kenchington
Date: 2003 Sep 7, 23:01 -0300
Peter, I really should leave this alone, since I am confident that it is clear to just about everyone on the list bar (apparently) yourself, but the issue being bounced around is _not_ an ambiguity. It is an estimation error. While I intend to buy a copy, I do not have the book in question. Hence, I cannot be sure of just what it says. However, the instructions for resolving the ambiguity which you keep on referring to would seem to be just that: instructions for resolving an ambiguity (presumably between quadrants). They are not, by the author's own admission, instructions for avoiding the estimation error which George has identified. As you note, this has become a huge kerfuffle over not very much at all. The not very much is a warning to users that one particular method has the potential to introduce significant errors under certain well-defined conditions. That should be straightforward. The kerfuffle comes from your insistence, and nobody else's, on making a big issue over this one, straightforward point. Indeed, you have now made such an issue of it that you have insisted on inserting your same message into a distinct thread, which I had given a new subject line precisely because I wanted to be able to deal with the implications of an erroneous azimuth estimate (regardless of the origin of that error) without being drawn into your persistent insistence on ambiguities where there are errors. Unfortunately, I failed. Trevor Kenchington Peter Fogg wrote: > What seems so unfair about this huge kerfuffle (about not very much at all) > is that if only the Weir Diagrams were on offer then that would presumably > have been just fine with the critics - haven't heard about their > shortcomings. But since another, simpler method is also provided that works, > once again, just fine in the vast majority of cases and has instructions > provided for resolving ambiguity near the prime vertical then the whole > method is denounced as 'VERY bad'. Which is nonsense. -- Trevor J. Kenchington PhD Gadus@iStar.ca Gadus Associates, Office(902) 889-9250 R.R.#1, Musquodoboit Harbour, Fax (902) 889-9251 Nova Scotia B0J 2L0, CANADA Home (902) 889-3555 Science Serving the Fisheries http://home.istar.ca/~gadus