diff --git a/script/optics/FocusYRotScan.py b/script/optics/FocusYRotScan.py
index e5ed7ed2..5119ed8b 100644
--- a/script/optics/FocusYRotScan.py
+++ b/script/optics/FocusYRotScan.py
@@ -7,7 +7,7 @@ set analyser parameters separately!
 changes
 -------
 
-2022-06-22 implement fly scan
+2022-06-22 implement fly scan: not supported by positioner!
 """
 
 import math
@@ -15,7 +15,7 @@ set_exec_pars(compression=True)
 
 # adjust the following parameters
 DISTANCE = 0.2
-STEPS = 0.002
+STEPS = 100
 LATENCY = 0.5
 ENDSCAN = False
 
@@ -27,7 +27,7 @@ SENSORS = (Counts, SampleCurrent, RefCurrent, MachineCurrent, Scienta.dataMatrix
 STARTPOS = (-DISTANCE / 2.0)
 ENDPOS = (DISTANCE / 2.0)
 RELATIVE = True
-FLY_SCAN = True
+FLY_SCAN = False  # fly scan not supported by positioner
 
 adjust_sensors()
 set_adc_averaging()