28 Jun
2004
28 Jun
'04
4:43 p.m.
On Mon, Jun 28, 2004 at 08:20:20AM -0700, Jo Walsh wrote:
On Mon, Jun 28, 2004 at 06:48:23AM -0400, IvorW
wrote:
http://www.wgs84.com/wgs84/wgs84.htm # World Geodetic System 1984
My reasons for wanting access to different systems is that not all
countries may be served by the same map sites. The London Openguide
works well with the use of Streetmap.co.uk, but this is no-use when
you move to Belfast (Different Grid System and you can't get os_x/y
from Streetmap).
I'm just thinking of being able to use the available data, and not
limit the software to those with GPS devices.
Stephen
I thought that you needed different ellipsoids
for different parts of the globe.
wgs84 or nad83 may work well for California, but I doubt if they would for Europe.
no, wgs84 is a global model. streetmap.co.uk gives you lat and long back in wgs84. you
need to worry about the different archaic reference datums used in different countries
grid projections only when projecting geodata onto flat maps that are already
georeferenced according to the other projection.
UTM is where this makes a difference for different countries grid systems - i
wouldn't know my own local mapping agency projection, though...
i would send a link with better metainfo but have to run...