Index: trunk/MagicSoft/Mars/macros/mergecamera.C
===================================================================
--- trunk/MagicSoft/Mars/macros/mergecamera.C	(revision 1865)
+++ trunk/MagicSoft/Mars/macros/mergecamera.C	(revision 1869)
@@ -8,4 +8,11 @@
 void mergecamera(Char_t *in="Proton*root", Char_t *out="all.root")
 {
+  cout << endl
+       << "WARNING: this macro merges camera output files, but the" << endl
+       << "Run headers of the resulting file are those of the first" <<endl
+       << "merged file, and so do not represent the whole of the" << endl
+       << "merged events. Be careful not to mix files with different" << endl
+       << "parameters (primary, theta...)." << endl << endl;
+
   //
   // Open output file: