diff --git a/MJOLNIR/Geometry/Instrument.py b/MJOLNIR/Geometry/Instrument.py
index 5ed4b804..7fdcd4cf 100644
--- a/MJOLNIR/Geometry/Instrument.py
+++ b/MJOLNIR/Geometry/Instrument.py
@@ -636,7 +636,7 @@ def generateCalibration(self,Vanadiumdatafile,A4datafile=False,savelocation='cal
                                             plt.ioff
                                         plt.figure()
                                         plt.scatter(EiLocal,binPixelData)
-                                        plt.plot(Ei,Gaussian(Ei,*guess))
+                                        plt.plot(Ei,Gaussian(Ei,*guess,0.0))
                                     
                                         plt.savefig(savelocation+'/{}_pixels/Detector{}_{}.png'.format(detpixels,i,k),format='png',dpi=150)
                                         plt.close()