4

I have gpx file (track) in WGS84 (EPSG: 4326) coordinate system from Garmin GPSMAP 62 which is right projected in BaseCamp and MapSource. When I save track as *.GPX and import it to QGIS and use Settings/Project properties/Coordinate Reference System/ and set as EPSG:3787 I get a wrong projected track (cca 300 m western of right position). Thanks!

6

First, have you checked that the GPX layer has CRS EPSG:4326?

To see if your track is correct you can install openlayers plugin, and show your track on top of Google satellite or OpenStreetMap.

EPSG:3787 is ment for Slovenia, deprecated by EPSG since 2009 (look for change request EPSG::2009.015), and should be replaced by EPSG:3911 and 3912. These are incorporated in latest GDAL 1.9.2 coming with Qgis Master.

Check if your proj string is:

+proj=tmerc +lat_0=0 +lon_0=15 +k=0.9999 +x_0=500000 +y_0=-5000000 +ellps=bessel +towgs84=577.326,90.129,463.919,5.137,1.474,5.297,2.4232 +units=m +no_defs

This might help you understand slovenian problems:

http://lists.maptools.org/pipermail/proj/2009-May/004652.html

http://lists.maptools.org/pipermail/proj/2009-March/004485.html

http://osgeo-org.1560.n6.nabble.com/Similar-datum-transforms-for-MGI-differ-too-much-td3843773.html

http://www.spatial-analyst.net/wiki/index.php?title=MGI_/_Balkans_coordinate_systems

Maybe

+proj=tmerc +lat_0=0 +lon_0=15 +k=0.9999 +x_0=500000 +y_0=-5000000 +ellps=bessel +towgs84=426.9,142.6,460.1,4.91,4.49,-12.42,17.1 +units=m +no_defs

fits better for you. Qgis Master offers EPSG:3912:

+proj=tmerc +lat_0=0 +lon_0=15 +k=0.9999 +x_0=500000 +y_0=-5000000 +ellps=bessel +towgs84=682,-203,480,0,0,0,0 +units=m +no_defs

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.