diff --git a/script/optics/microfocus/ManipulatorFlyScan.py b/script/optics/microfocus/ManipulatorFlyScan.py
index 6daaca76..9ead4c16 100644
--- a/script/optics/microfocus/ManipulatorFlyScan.py
+++ b/script/optics/microfocus/ManipulatorFlyScan.py
@@ -25,7 +25,7 @@ ZIGZAG = False
 ENDSCAN = False
 
 step_time = 0.1
-fly_time = (RANGE[1] - RANGE[0]) / SPEED
+fly_time = abs((RANGE[1] - RANGE[0]) / SPEED)
 STEPS = int(fly_time / step_time) + 1
 print "scan time: ", fly_time