My cave survey freeware can export its cave map in DXF format, where XYZ coordinates are orthogonal meters from the origin station (0,0,0 by default). A user asks me to export this DXF so that it geolocates itself properly in QGIS. a georeference is available for the origin station in the raw survey data. How can I pass this geodesic information into the DXF file for QGIS? I suggested my user to alter the origin station coordinates to match its WGS84 UTM coordinates, but that does not seem to work. He also tried changing these origin station coordinates to latitude/longitude degrees, to no avail.

Can a DXF be georeferenced so that it opens and geolocates itself correctly in QGIS without any further user intervention like using bending plugins or creating shapefiles?

  • the answer should be to create a local SRS with proj and use for convert to WGS84 UTM. Expecting a local CS has origin closed to the study area. can you report the extent, and where you expect the data (lon/lat of origin station) ? – Hugo Roussaffa - GeoDatup Oct 10 '17 at 18:10
  • Maybe related: gis.stackexchange.com/questions/83861/… (works outside Arcgis too). – AndreJ Oct 10 '17 at 19:07

If your dxf map has a coordinate system correctly assigned, upon import into QGIS, you should have an option to assign the same coordinate system (if it is one of the options available in QGIS) and the dxf will be correctly georeferenced.

Figure out the coordinate system issue with the freeware (externally) before importing into QGIS.

Your Answer

