Pathfinder Office (PFO)
When exporting position files, Pathfinder Office treats input positions (*.SSF, *.cor) as referencing the WGS 1984 datum, even if the positions actually reference a different datum, e.g. NAD83 (2011). As a result, you cannot work with map projections in Pathfinder Office the same way as in professional GIS software.
If your positions reference a datum that is not WGS 1984 or the comparable ITRF, specify an output datum in position export setup that will not trigger a datum transformation. After position export is completed, use GIS software tool, e.g. the “Define Projection” tool in ArcGIS software, to enter the correct map projection information in the exported GIS file.
For example, if your *.cor file (corrected position file) reference the NAD83 (2011) datum, set output coordinate system datum ITRF 2000 (as of August 2019). After position export is completed, use the “Define Projection” tool to define the correct datum for the output GIS data file (NAD83 (2011)).
In the above example, if you set output coordinate system datum NAD83 (2011), Pathfinder Office will apply a WGS1984-to-NAD83 (2011) transformation to the output positions and result in a position shift in the output. The shift can be as much as 1 meter (3.5 feet), as shown in the graphic below (Note, positions corrected using CORS station position from base file reference the NAD 83 (2011) datum; positions corrected using CORS station position from base station list reference ITRF 2000. See tab “Exporting Positions” for details):
If your positions are corrected real-time using an external correction source that references a different datum and the datum of the correction source is specified in TerraSync, the corrected positions references the WGS 1984 datum. TerraSync transforms incoming positions to the datum used by the correction source and back to the WGS 1984 datum after positions are corrected.
If your positions are post-processed in Pathfinder Office, the positions reference the datum of correction source.
To learn if Pathfinder Office performs a datum transformation between WGS 1984 and a different datum:
- Click the “Utilities” menu –> “Other” –> “Coordinate System Manager”.
- Click the “Datum Transformations” tab.
- Click the datum in question on the left pane, then right-click the transformation associated with the datum on the right pane and click “Properties” to see datum transformation parameters. In the examples below, the transformation parameters indicate Pathfinder Office does not apply datum transformation when moving positions referencing the WGS 1984 datum to the NAD 1983 (Conus) datum. There is also no transformation between WGS 1984 and ITRF 2000.