diff --git a/src/aare/devices/jfjoch.py b/src/aare/devices/jfjoch.py
index 7cc07841..22eca973 100644
--- a/src/aare/devices/jfjoch.py
+++ b/src/aare/devices/jfjoch.py
@@ -201,8 +201,8 @@ class JFJochWrapper:
             detect_ice_rings=True,
             async_start=async_start,
             smargon=smargon_phi_chi,
-            #beam_size_x_um=s.diffraction.beam_size_x,
-            #beam_size_y_um=s.diffraction.beam_size_y,
+            beam_size_x_um=s.geom.beam_size_mm.x * 1000.0,
+            beam_size_y_um=s.geom.beam_size_mm.y * 1000.0,
         )
 
         # settup grid or goniometer settings adn add to dataset settings