diff --git a/src/user_interface.py b/src/user_interface.py
index f893266..55cd117 100644
--- a/src/user_interface.py
+++ b/src/user_interface.py
@@ -1860,9 +1860,8 @@ class CalibrateMagnetometerComplete(Frame):
                 return
             self.calibration_raw_results = raw_data
 
-            # Note: Imported data must already have the MGM and set field aligned!
-            ui_print('Imported data transformed with unity matrix. Make sure, MGM and set field of file are in same COS!')
-            mgm_to_helmholtz_cos_trans = [[1, 0, 0], [0, 1, 0], [0, 0, 1]]
+            # Get transformation matrix from GUI and transform data
+            mgm_to_helmholtz_cos_trans = [[x.get() for x in row] for row in self.mgm_to_helmholtz_cos_trans]
             # Execute calibration function and display results
             sensor_parameters, mag_x_set, mag_y_set, mag_z_set, mag_x_m, mag_y_m, mag_z_m, cal_x, cal_y, cal_z, mag_amp_avg_set = MagnetometerCalibrationComplete.solve_system(
                 raw_data, mgm_to_helmholtz_cos_trans)