typo

lib/imaging.py

@@ -174,9 +174,8 @@ def compute_mot_number(image, QE, gain, exposure_time, solid_angle,
         detuning, intensity_parameter):
     if image.max() >= 2**16:
         print("WARNING: image may contain clipping")
-    electron_rate = im.sum() * 16
+    electron_rate = image.sum() * 16
     photon_rate = electron_rate / gain / QE / solid_angle / exposure_time
-
     Y = 29.1e6 * 2 * np.pi # transition linewidth; s^-1
     l = 399e-9 # transition wavelength; m
     I_sat = (Y * H * C * np.pi) / (3 * l**3)