diff --git a/cscripts/csobsinfo.py b/cscripts/csobsinfo.py
index 585e784..00ae10d 100755
--- a/cscripts/csobsinfo.py
+++ b/cscripts/csobsinfo.py
@@ -137,16 +137,16 @@ class csobsinfo(ctools.cscript):
         
         # Initialise arrays to store certain values for reuse
         # Todo, think about using a python dictionary
-        self.offsets  = []
-        self.zeniths  = []
-        self.azimuths = []
+        self.m_offsets  = []
+        self.m_zeniths  = []
+        self.m_azimuths = []
         self.pnt_ra   = []
         self.pnt_dec  = []
         obs_names     = []
         
         # Initialise output to be filled
-        self.ebounds   = gammalib.GEbounds()
-        self.gti       = gammalib.GGti()
+        self.m_ebounds   = gammalib.GEbounds()
+        self.m_gti       = gammalib.GGti()
         ontime         = 0.0
         livetime       = 0.0
         n_events       = 0
@@ -197,10 +197,10 @@ class csobsinfo(ctools.cscript):
             
             # If avaliable append energy boundaries
             if obs_bounds.size() > 0 : 
-                self.ebounds.merge(obs_bounds.emin(),obs_bounds.emax())
+                self.m_ebounds.append(obs_bounds.emin(),obs_bounds.emax())
             
             # Append time interval
-            self.gti.merge(obs_gti.tstart(), obs_gti.tstop())
+            self.m_gti.append(obs_gti.tstart(), obs_gti.tstop())
             
             # increment global livetime and ontime
             ontime += obs.ontime()
@@ -271,18 +271,18 @@ class csobsinfo(ctools.cscript):
                 # Log offset if possible
                 if self.m_offset:
                     offset = pnt_dir.dist_deg(self.obj_dir)
-                    self.offsets.append(offset)
+                    self.m_offsets.append(offset)
                     self.log.parformat("Offset")
                     self.log("%.2f" % (offset))
                     self.log("\n")
                 else:
-                    self.offsets.append(-1.0)
+                    self.m_offsets.append(-1.0)
                     
                 # Retrieve zenith and azimuth and store for later use
                 zenith = obs.pointing().zenith()
                 azimuth = obs.pointing().azimuth()
-                self.zeniths.append(zenith)
-                self.azimuths.append(azimuth)
+                self.m_zeniths.append(zenith)
+                self.m_azimuths.append(azimuth)
                 
                 # Log Zenith and Azimuth if required
                 if self.logExplicit():
@@ -317,15 +317,15 @@ class csobsinfo(ctools.cscript):
         # Log mean offset if possible
         if self.m_offset:
             self.log.parformat("Mean offset angle")
-            self.log("%.2f" % (sum(self.offsets)/len(self.offsets)))
+            self.log("%.2f" % (sum(self.m_offsets)/len(self.m_offsets)))
             self.log("\n")
         
         # Log mean azimuth and zenith angle
         self.log.parformat("Mean zenith angle")
-        self.log("%.2f" % (sum(self.zeniths)/len(self.zeniths)))
+        self.log("%.2f" % (sum(self.m_zeniths)/len(self.m_zeniths)))
         self.log("\n")
         self.log.parformat("Mean azimuth angle")
-        self.log("%.2f" % (sum(self.azimuths)/len(self.azimuths)))
+        self.log("%.2f" % (sum(self.m_azimuths)/len(self.m_azimuths)))
         self.log("\n")
         
         # Log name of observations if requested
@@ -340,25 +340,25 @@ class csobsinfo(ctools.cscript):
         # Log energy range
         self.log.header3("Energy range")
         self.log.parformat("Emin")
-        if self.ebounds.size() == 0:
+        if self.m_ebounds.size() == 0:
             self.log("undefined")
         else:
-            self.log(str(self.ebounds.emin()))
+            self.log(str(self.m_ebounds.emin()))
         self.log("\n")
         self.log.parformat("Emax")
-        if self.ebounds.size() == 0:
+        if self.m_ebounds.size() == 0:
             self.log("undefined")
         else:
-            self.log(str(self.ebounds.emax()))
+            self.log(str(self.m_ebounds.emax()))
         self.log("\n\n")
         
         # Log time range
         self.log.header3("Time range")
         self.log.parformat("Start [MJD]")
-        self.log(str(self.gti.tstart().mjd()))
+        self.log(str(self.m_gti.tstart().mjd()))
         self.log("\n")
         self.log.parformat("Stop [MJD]")
-        self.log(str(self.gti.tstop().mjd()))
+        self.log(str(self.m_gti.tstop().mjd()))
         self.log("\n")  
         
         # Log ontime and livetime in different units      
@@ -408,31 +408,31 @@ class csobsinfo(ctools.cscript):
         """
         Return zenith angles
         """
-        return self.zeniths
+        return self.m_zeniths
     
     def azimuths(self):
         """
         Return azimuth angles
         """
-        return self.azimuths
+        return self.m_azimuths
     
     def offsets(self):
         """
         Return offset angles
         """
-        return self.offsets
+        return self.m_offsets
 
     def ebounds(self):
         """
         Return energy boundaries
         """
-        return self.ebounds
+        return self.m_ebounds
     
     def gti(self):
         """
         Return good time intervals
         """
-        return self.gti
+        return self.m_gti
             
     def execute(self):
         """