diff --git a/src/ctbin/ctbin.cpp b/src/ctbin/ctbin.cpp
index bc28262..de35711 100644
--- a/src/ctbin/ctbin.cpp
+++ b/src/ctbin/ctbin.cpp
@@ -206,9 +206,8 @@ void ctbin::clear(void)
  ***************************************************************************/
 void ctbin::execute(void)
 {
-    // Read ahead output filename so that it gets dumped correctly in the
-    // parameters log
-    m_outfile = (*this)["outfile"].filename();
+    // Signal that some parameters should be read ahead
+    m_read_ahead = true;
 
     // Bin the event data
     run();
@@ -439,6 +438,12 @@ void ctbin::get_parameters(void)
     m_nxpix    = (*this)["nxpix"].integer();
     m_nypix    = (*this)["nypix"].integer();
 
+    // Optionally read ahead parameters so that they get correctly
+    // dumped into the log file
+    if (m_read_ahead) {
+        m_outfile = (*this)["outfile"].filename();
+    }
+
     // Return
     return;
 }
@@ -614,7 +619,8 @@ void ctbin::init_members(void)
     // Initialise protected members
     m_obs.clear();
     m_infiles.clear();
-    m_use_xml = false;
+    m_use_xml    = false;
+    m_read_ahead = false;
 
     // Set logger properties
     log.date(true);
@@ -647,9 +653,10 @@ void ctbin::copy_members(const ctbin& app)
     m_nypix    = app.m_nypix;
 
     // Copy protected members
-    m_obs      = app.m_obs;
-    m_infiles  = app.m_infiles;
-    m_use_xml  = app.m_use_xml;
+    m_obs        = app.m_obs;
+    m_infiles    = app.m_infiles;
+    m_use_xml    = app.m_use_xml;
+    m_read_ahead = app.m_read_ahead;
 
     // Return
     return;
diff --git a/src/ctbin/ctbin.hpp b/src/ctbin/ctbin.hpp
index e057f28..c945890 100644
--- a/src/ctbin/ctbin.hpp
+++ b/src/ctbin/ctbin.hpp
@@ -80,24 +80,25 @@ protected:
                                    const std::string&     outfile) const;
 
     // User parameters
-    std::string              m_evfile;   //!< Input event list or XML file
-    std::string              m_outfile;  //!< Output counts map or XML file
-    std::string              m_prefix;   //!< Prefix for multiple counts maps
-    double                   m_emin;     //!< Lower energy
-    double                   m_emax;     //!< Upper energy
-    int                      m_enumbins; //!< Number of energy bins
-    std::string              m_proj;     //!< WCS projection
-    std::string              m_coordsys; //!< Coordinate system
-    double                   m_xref;     //!< Longitude reference coordinate
-    double                   m_yref;     //!< Latitude reference coordinate
-    double                   m_binsz;    //!< Pixel size
-    int                      m_nxpix;    //!< Number of pixels in longitude
-    int                      m_nypix;    //!< Number of pixels in latitude
+    std::string              m_evfile;     //!< Input event list or XML file
+    std::string              m_outfile;    //!< Output counts map or XML file
+    std::string              m_prefix;     //!< Prefix for multiple counts maps
+    double                   m_emin;       //!< Lower energy
+    double                   m_emax;       //!< Upper energy
+    int                      m_enumbins;   //!< Number of energy bins
+    std::string              m_proj;       //!< WCS projection
+    std::string              m_coordsys;   //!< Coordinate system
+    double                   m_xref;       //!< Longitude reference coordinate
+    double                   m_yref;       //!< Latitude reference coordinate
+    double                   m_binsz;      //!< Pixel size
+    int                      m_nxpix;      //!< Number of pixels in longitude
+    int                      m_nypix;      //!< Number of pixels in latitude
 
     // Protected members
-    GObservations            m_obs;      //!< Observation container
-    std::vector<std::string> m_infiles;  //!< Input event filenames
-    bool                     m_use_xml;  //!< Use XML file instead of FITS file
+    GObservations            m_obs;        //!< Observation container
+    std::vector<std::string> m_infiles;    //!< Input event filenames
+    bool                     m_use_xml;    //!< Use XML file instead of FITS file
+    bool                     m_read_ahead; //!< Read ahead parameters
 };
 
 #endif /* CTBIN_HPP */