Import a file with a different CRS

When you import a file that uses a different Coordinate Reference System (CRS) than your current project, Pythagoras needs to know which CRS the source file uses.
If the source CRS is known via a prj-file, Pythagoras automatically transforms the imported data to the document CRS.

If not, by selecting the file's CRS in the Control Panel, Pythagoras automatically transforms the data to the CRS of the active document.

For example, your active drawing uses Belgium / Lambert 2008 (EPSG:3812), while the received data is in Belgium / Lambert 72 (EPSG:31370). The goal is to import the data into the correct position in the active project.

STEPS

1. Verify the document CRS

Go to Settings > Document Settings > CRS.

Confirm that the document is using the correct CRS, for example Belgium / Lambert 2008 (EPSG:3812).

• NOTE

  If the imported file contains a valid .prj file, Pythagoras automatically detects the source CRS. In that case, you can skip step 2.

  If the file has no .prj file, or if the CRS cannot be determined, select the source CRS manually in the Control Panel before importing.

2. Select the source file CRS in the Control Panel

In the Control Panel, select the CRS of the file you want to import, for example Belgium / Lambert 72 (EPSG:31370).

3. Import the file

Go to File > Import.

Select the appropriate import format for the file you received. Pythagoras transforms the imported data from the source CRS to the active document CRS.

For example, data in Belgium / Lambert 72 (EPSG:31370) is transformed to Belgium / Lambert 2008 (EPSG:3812).
From version 16 onwards, this transformation uses the rdatrans2018.gsb NTv2 grid file when it is available.

4. Verify the imported data

Zoom to the imported objects.

Check that they are positioned correctly.

If necessary, compare the result with a known control point or a background layer.

5. Set the working CRS

After the import, in the Control Panel, select the coordinate reference system you want to use while continuing your work. This changes the coordinates displayed in the Control Panel and the coordinates used for new input. The imported data remains in the document CRS.

RESULT

The imported data has been transformed to the document CRS and is correctly positioned in your project.

If you want to change the coordinate reference system of an existing drawing, see Change a drawing to a different CRS.