Importing Digitized Coordinates

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Module information
Modules BESA Research Basic or higher
Version 5.2 or higher

How do I import digitized electrode coordinates and head surface points

Digitized electrode locations can be provided in a surface point file (extension *.sfp) in ASCII format. It is recommended that the first three digitized coordinates are the fiducials (fiduciary points), labeled ‘FidT9’, ‘FidT10′, FidNz’, followed by electrodes, and possibly additional skin points. A detailed description of the file and how to import it is given in the BESA help files (chapter: Working with Electrodes and Surface Locations). An example sfp file could look like this:

FidNz -10.89 0.04 -4.30

FidT9 -0.61 -7.78 -5.24

FidT10 -0.70 7.34 -5.86

E1 -1.52 -2.31 6.98

E2 -1.65 -7.67 2.54

E3 -4.26 -8.31 -3.86

...

The file is read in using the dialog "Channel and digitized head surface point information" in menu "File → Head Surface Points and Sensors → Load Coordinate Files" (use 'CTRL-L' key on the keyboard).

How do I check the result

You can check on the correct reading of the file using the View Head Surface points window (menu "File → Head Surface Points and Sensors → View" or "V" on the keyboard).

See also the article Verify Electrode Coordinates.

Digitized head surface points dialog.png