Re: GPS to grid reference



Roger wrote:

These days lists of peaks are everywhere and your guess is as good as
mine as to which flavour of grid reference they use as I don't think
any of them spell it out.

If you compare Dawson to Dewey you'll find that many of the same summits
have different 6 figure GRs. After close examination it's clear that Dawson
uses the SW corner while Dewey tries to estimate the point itself. If you
use Dewey's grid refs and assume them to refer to a square rather than a
point, you'll often find yourself in the wrong square.

And there a surprising number of peaks with
multiple summits of approximately the same height all within 140m of
each other.

You really need at least 8 figures for those.

Using a gps doesn't necessarily help overmuch. In entering a 6 figure
reference do you add 00 to each co-ordinate or 50?

I routinely added 50 myself, but now I don't bother, I'd rather set a more
accurate GR for myself. In these days of GPS and digital mapping, I've no
longer got any use for 6 figure GRs anymore, I don't see why anyone with a
GPS would bother with them, unless they have no alternative. No doubt
they're still handy for map and compass users who seem to enjoy that lack of
accuracy, but once you've got used to using a GPS and routinely getting to
within 10m of a point, it's very hard to go back to 6 figure GRs. In fact, I
now consider an error of 30 or 40m to be appallingly bad.

Of course, in practice this isn't a problem in clear visibility, but at
night or in very thick fog, it can sometimes be an issue.

Paul
--
http://www.wilderness-wales.co.uk/
http://www.wilderness-wales.co.uk/weblog/


.



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