Seems to be an underlying problem with proj4: echo "59 21" | proj "+init=epsg:3021" | invproj "+init=epsg:3021"
58d49'47.733"E 21d2'54.745"N And that's without doing the datum shift part. P On Wed, Aug 11, 2010 at 1:10 PM, Erik Rehn <e...@slagkryssaren.com> wrote: > Hello Postgis Users! > > This is my first post on this list so I will start by asking > a simple (and probably stupid) question. :) > > While using ST_AsKml() to produce an overlay for Google Earth I > noticed that all my geometries where shifted slightly south-east. > I figured this had something to do with the transformation between > the projection that my geometries are stored in (SRID 3021) and WGS84 (4326) > that is outputted by ST_AsKml() > > Just to test I ran this: > > SELECT ST_AsText( > ST_Transform( > ST_Transform( > ST_GeomFromText('POINT(59 18)',4326), > 3021), > 4326)); > > I input a point in WGS84 (59,18), transforms it to 3021 and then back to > WGS84. The result I get is: > POINT(58.8672757036296 18.0394763349359) > > Can anyone explain this? Am I missing something regarding ST_Transform()? > > Im running Postgis 1.5 on Windows. > > Thank you for any help! > /Erik > > -- > Erik Rehn > Slagkryssaren > e...@slagkryssaren.com > www.slagkryssaren.com > _______________________________________________ > postgis-users mailing list > postgis-users@postgis.refractions.net > http://postgis.refractions.net/mailman/listinfo/postgis-users > _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users