Index: trunk/Mars/mcore/DrsCalib.h
===================================================================
--- trunk/Mars/mcore/DrsCalib.h	(revision 17243)
+++ trunk/Mars/mcore/DrsCalib.h	(revision 17248)
@@ -1377,5 +1377,5 @@
     }
 
-    std::string WriteFitsImp(const std::string &filename, uint32_t night, const std::vector<float> &vec) const
+    std::string WriteFitsImp(const std::string &filename, const std::vector<float> &vec, uint32_t night=0) const
     {
         const size_t n = 1440*1024*4 + 1440*fRoi*2 + fNumTm*fRoi*2 + 3;
@@ -1407,5 +1407,6 @@
 
         file.SetDefaultKeys();
-        file.SetInt("NIGHT", night, "Night as int");
+        if (night>0)
+            file.SetInt("NIGHT", night, "Night as int");
 
         file.SetStr("DATE-OBS", fDateObs, "First event of whole DRS calibration");