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Re: Sextant Positions versus Map Datums?
From: Pierre Boucher
Date: 2002 Jan 17, 10:11 PM
From: Pierre Boucher
Date: 2002 Jan 17, 10:11 PM
>Interestingly enough I have gotten a response on this from the >ask@usgs.gov folks. > >They directed me to a datum conversion program (CORPSCAN) which is >publicly available but mainly limited to NAD27 and NAD84, NAD84 arguably >being "substantially identical" etcetera to the later US domestic datums. Never heard of NAD84!!!! maybe you meant WGS84 which is equivalent to NAD83 >Anyway...using CORPSCAN in the area of N40d 35.703m, W073d 29.596m and >inputting that as NAD84, that position shifts by some 38 meters when >translated to NAD27. (38 meters found by taking the offsets produced by >the program and calculating the length of the diagonal.) You don't need any software is you have a GPS. Just switch from one datum to another on any waypoint that you have in the machine. You will see the shift in position. Pierre Boucher Pierre Boucher N Commandant/Retir� Escadrille des Mille-�les
