diff --git a/script/optics/ExitSlitYScanKei.py b/script/optics/ExitSlitYScanKei.py
index 5d43a01c..5bb9fbac 100644
--- a/script/optics/ExitSlitYScanKei.py
+++ b/script/optics/ExitSlitYScanKei.py
@@ -37,7 +37,7 @@ time.sleep(0.1)
 
 #caput(KEI_DIODE + "READSCAN.SCAN", 0)
 #caput(KEI_DIODE + "NPLC", 1)
-caput(KEI_DIODE + "NAVG", 10)
+caput(KEI_DIODE + "NAVG", 50)
 #caput(KEI_DIODE + "TCOUNT", 1)
 caput(KEI_DIODE + "RANGE", 6) # 200 nA
 time.sleep(1.0)
@@ -63,6 +63,7 @@ def trig():
     caput(KEI_DIODE + "DOFETCH", 1)
     #caput(KEI_RMU + "DOFETCH", 1)
 
-lscan(POSITIONERS, SENSORS, STARTPOS, ENDPOS, STEPS, LATENCY, before_read=trig, after_read=after_readout)
-
-caput(KEI_DIODE + "DORESET", 1)
+try:
+    lscan(POSITIONERS, SENSORS, STARTPOS, ENDPOS, STEPS, LATENCY, before_read=trig, after_read=after_readout)
+finally:
+    caput(KEI_DIODE + "DORESET", 1)