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hello, & what datum?

Posted: 09 August 03 1:44 pm
by baseline benny
Hi,
heard about geocaching a couple of years ago but have just now borrowed a mates gpsr to try it out. His etrex has the datum set to "Aus Geod '84". Is this what I want it set to for geocaching?

thanks,
baseline

Posted: 09 August 03 3:25 pm
by maccamob
G'day Benny. Geocaching coordinates are based on the international WGS84 Datum (you'll see it given in brackets after the coordinates on each cache page on geocaching.com).<p>

There are three Australian datums - Australian Geodetic 1966, Australian Geodetic 1984 and Australian Geocentric 1994. The last is compatible with WGS84, but you will get some position differences between WGS84 and the earlier Australian ones that can be as much as 200m with ADG66.<p>

Always set the GPS to WGS84 for geocaching, but if you want to compare your GPS position with a paper map, set it to the same datum as the map.<p>

Hope you enjoy the experience.

Posted: 10 August 03 12:07 pm
by baseline benny
maccamob wrote:Always set the GPS to WGS84 for geocaching, but if you want to compare your GPS position with a paper map, set it to the same datum as the map.
Thanks,<br>
<br>
Now I'll go try find a cache! ;-)<br>
<br>
baseline benny.