diff --git a/Code/Mantid/scripts/Reflectometry/isis_reflectometry/quick.py b/Code/Mantid/scripts/Reflectometry/isis_reflectometry/quick.py
index 9191165acc6e..fe60a3b13907 100644
--- a/Code/Mantid/scripts/Reflectometry/isis_reflectometry/quick.py
+++ b/Code/Mantid/scripts/Reflectometry/isis_reflectometry/quick.py
@@ -195,12 +195,13 @@ def quick_explicit(run, i0_monitor_index, lambda_min, lambda_max,  background_mi
             source=inst.getSource()
             beamPos = sampleLocation - source.getPos()
             PI = 3.1415926535
-            theta = inst.getComponentByName(detector_component_name).getTwoTheta(sampleLocation, beamPos)*180.0/PI/2.0
+            theta = groupGet(str(_sample_ws),'samp','theta')
+            if not theta:
+                theta = inst.getComponentByName(detector_component_name).getTwoTheta(sampleLocation, beamPos)*180.0/PI/2.0
             print "Det location: ", detLocation, "Calculated theta = ",theta
             if correct_positions:  # detector is not in correct place   
                 # Get detector angle theta from NeXuS
                 logger.information('The detectorlocation is not at Y=0')
-                theta = groupGet(run_ws,'samp','theta')
                 print 'Nexus file theta =', theta
                 IvsQ = l2q(IvsLam, detector_component_name, theta, sample_component_name)
             else: