diff --git a/ale/drivers/msl_drivers.py b/ale/drivers/msl_drivers.py
index 25ef1d8ca0f4e0dccb3c765494a258af54b4c0f0..e826e560ff3cf5628da351f7c6d22ab96c9ad342 100644
--- a/ale/drivers/msl_drivers.py
+++ b/ale/drivers/msl_drivers.py
@@ -105,7 +105,7 @@ class MslMastcamPds3NaifSpiceDriver(Cahvor, Framer, Pds3Label, NaifSpice, NoDist
         : list<double>
           focal plane to detector samples
         """
-        return [1/self.pixel_size, 0, 0]
+        return [0, 0, 1/self.pixel_size]
     
     @property
     def sensor_model_version(self):
diff --git a/tests/pytests/test_msl_drivers.py b/tests/pytests/test_msl_drivers.py
index 7b58c1a3c10b13ba6c7c691cfc7e3aff8bdc84f2..986dbd2094b72e0f348d2a6c987b9069d319585b 100644
--- a/tests/pytests/test_msl_drivers.py
+++ b/tests/pytests/test_msl_drivers.py
@@ -43,6 +43,6 @@ class test_mastcam_pds_naif(unittest.TestCase):
     def test_focal2pixel_samples(self):
         with patch('ale.drivers.msl_drivers.spice.bods2c', new_callable=PropertyMock, return_value=-76220) as bods2c, \
              patch('ale.drivers.msl_drivers.spice.gdpool', new_callable=PropertyMock, return_value=[100]) as gdpool:
-            np.testing.assert_allclose(self.driver.focal2pixel_samples, [137.96844341513602, 0, 0])
+            np.testing.assert_allclose(self.driver.focal2pixel_samples, [0, 0, 137.96844341513602])
             bods2c.assert_called_with('MSL_MASTCAM_RIGHT')
             gdpool.assert_called_with('INS-76220_FOCAL_LENGTH', 0, 1)