NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: UTM to lat/lon formulas
From: George Huxtable
Date: 2003 Dec 14, 21:56 +0000
From: George Huxtable
Date: 2003 Dec 14, 21:56 +0000
I've got a pocket-calculator conversion working between lat/long and UTM, assuming the Clarke 1866 ellipsoid for North America. What's more, when I convert to UTM and back again it arrives at the original lat/long, within a skin-off-a-midge. That's a necessary test, but is not sufficient to show that the UTM values are in fact correct. In zone 15 (long 96 to 90 deg), if I take a position on the edge of the zone at- North 40.0 deg, West 90.0 deg, this gives me for UTM- x= 756155; y= 4431860 This is based on the assumption that 500000 has been added to all x values, so that on the centre-line of the zone (93 degrees) the x coordinate is 500000, to prevent negative values occurring. Is it near? George. ================================================================ contact George Huxtable by email at george@huxtable.u-net.com, by phone at 01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. ================================================================