diff --git a/site_ansto/instrument/TEST_SICS/tests/plot-tracking.py b/site_ansto/instrument/TEST_SICS/tests/plot-tracking.py
index 25aa866b..8be66ca1 100755
--- a/site_ansto/instrument/TEST_SICS/tests/plot-tracking.py
+++ b/site_ansto/instrument/TEST_SICS/tests/plot-tracking.py
@@ -6,19 +6,24 @@
 import numpy as np
 import matplotlib as mpl
 import matplotlib.pyplot as plt
+import argparse
 
 def make_delta(q):
-  delta_q = np.arange(len(q), dtype=np.float)
+  delta_q = np.zeros(len(q))
   delta_q[0] = 0.0
   for i in range(1, len(q)):
     delta_q[i] = q[i] - q[i - 1]
   return delta_q
 
-if False:
-  data = np.genfromtxt("s2_tracking.csv", delimiter=",", skip_header=1,
-    names=['time', 'position', 'steps', 'counts'])
+parser = argparse.ArgumentParser()
+parser.add_argument("csv_file", help="TrackingFile.csv", nargs="?")
+args = parser.parse_args()
+if args.csv_file:
+    csv_file = args.csv_file
 else:
-  data = np.loadtxt("s2_tracking.csv", delimiter=",", skiprows=1, unpack=True)
+    csv_file = "s2_tracking.csv"
+
+data = np.loadtxt(csv_file, delimiter=",", skiprows=1, unpack=True)
 
 t, p, s, c = data
 
@@ -36,11 +41,14 @@ delta_c = make_delta(c)
 fig = plt.figure()
 ax1 = fig.add_subplot(111)
 
-ax1.set_title("Motion Tracking")
-ax1.set_xlabel('position')
-ax1.set_ylabel('Steps/Count')
+ax1.set_title("Motion Tracking (" + csv_file + ")")
+ax1.set_xlabel("position (%.3f to %.3f)" % (p[0], p[-1]))
+ax1.set_ylabel("Steps/Count")
 
-delta_spc = np.arange(len(t), dtype=np.float)
+steps_per_count = ((s[-1] - s[0]) / (c[-1] - c[0]))
+print "StepsPerCount: %.6f" % steps_per_count
+
+delta_spc = np.zeros(len(t))
 for i in range(len(delta_spc)):
   if delta_c[i] == 0:
     delta_spc[i] = 0
@@ -52,9 +60,10 @@ if False:
   for i in range(len(t)):
     print "%4d: %18.6f %18.6f %18.6f %18.6f %18.6f" % (i, t[i], delta_t[i], delta_s[i], delta_c[i], delta_spc[i])
 
-ax1.plot(p, delta_spc, c='r', label='delta steps per count')
-ax1.plot(p, c / s / 70, c='b', label='counts / steps')
-
+ax1.plot(p, delta_spc - steps_per_count, c='r', label='delta steps per count')
+ax1.plot(p, (s - s[0])/(c - c[0]) - steps_per_count, c='b', label='steps / counts')
+ax1.get_xaxis().grid(True, 'both')
+ax1.get_yaxis().grid(True, 'both')
 leg = ax1.legend()
 
 plt.show()