Index: /trunk/FACT++/src/Converter.cc
===================================================================
--- /trunk/FACT++/src/Converter.cc	(revision 18612)
+++ /trunk/FACT++/src/Converter.cc	(revision 18613)
@@ -966,5 +966,5 @@
            break;
 
-       if (type=='S')
+       if (type=='S' || type=='N')
        {
            const string str(charSrc);
@@ -1061,8 +1061,9 @@
          case 'v':
          case 'S': //we skip the variable length strings
+         case 'N':
              continue;
 
          default:
-             throw runtime_error("GetFitsFormat - unknown FITS format.");
+             throw runtime_error(string("GetFitsFormat - unknown FITS format [")+it->first.first->name()[0]+"]");
          };