[Talk-GB] NPE Tracing Update

[Nick Burch]

On Wed, 14 Mar 2007, Barnett, Phillip wrote:
> Just started playing with the JOSM plugin - but how can I rectify the 
> maps? They don't really line up with GPS traces. I know I can drag the 
> layer around, (N,S,E,W) but they mostly seem to need skewing also.

I normally just use http://gpx.npemap.org.uk/ . With that, you calibrate 
for the centre section of 9 tiles. That normally ends up being accurate 
over the 9 tiles despite most errors. You then shuffle off to the next 
batch of 9, re-calibrate for their errors, and continue.

It works very well, but it is a two stage process (make gpx, then draw 
over it in josm)

Nick