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View Full Version : Which grid system ?



3wise
18th February 2005, 09:45 AM
As a newbie, can you tell me which grid system is normally used by members?
I see that both Lat/Long and NGR are given for cache locations.
Which one is preferred and why ?
Since I expect to carry an OS map, I fancy NGR. However, I wonder if resolution is any different for the various systems.

John Stead
18th February 2005, 10:03 AM
Lat/Long with the setting DD mm.mmm is the convention used for Geocaching as it is an international game. There is nothing to stop you using OSGB if you prefer and no significant different in accuracy, though some will argue that there is. The only snag which may by now have been addressed was that the grid references given on the cache descriptions used to have leading zeros stripped which caused confusion. The advantage of OSGB is that you can compare distances east and north directly.
Personally having used the OS for many years (I was a surveyor) I was at first uncomfortable with lat/long but rapidly adopted it for the sake of convenience in reading and downloading geocaching pages. If you want to see them side my side there is the excellent Waypoint Workshop which you can download from www.sheps.clara.net

3wise
18th February 2005, 07:20 PM
Thanks for the advice. I think I will keep it simple for a start and go with the more familiar OSGB ("NGR" ?). If I find cause to change later, so be it.

Bill D (wwh)
18th February 2005, 08:22 PM
One problem you'll encounter if you use OSGB is that when you're doing a multicache you'll be getting new co-ordinates in lat/long as you go along, and if you want to work entirely with OSGB you'll need some means of converting them out in the field. With most gps units, though, you can readily switch between OS grid references and lat/long, but remember to also change the datum, which should be WGS84 for lat/long and OSGB36 for OS grid refs, unless your gps does that automatically.