--- In Dan Dugan <> wrote:
>
> > It's worth noting that, when someone says that the get unreliable
> > readings near cliffs etc. the actual error is probably less than 50
> > metres. More than accurate enough for plotting which pond you recorded
> > at. Where I had problems with that was when trying to find a small
> > film canister cache hidden under a rock ledge 10 metres down an abseil
> > in our Morialta National Park. where I needed to go voer the cliff
> > within a couple of feet laterally of the correct location. BUT...as I
> > said, for plotting where you are in relation to a recording, I think
> > as long as you are getting a sat fix, then the error will be
> > acceptable.
>
> Well, in the case I described on the Upper Yosemite Falls Trail, track =
> points went scattering out across the valley at least a quarter of a
> mile. I'm not sure (I edited the track subsequently in software), but =
> they may have been correct in one dimension and not in another, i.e.
> as I moved along the trail the points followed my progress parallel to =
> the trail but jumped around perpendicularly.
>
> -Dan Dugan
>
perhaps you were in the 'shadow' of one
or more of the satellites being used?
clay
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