Index: trunk/ppTranslate/src/ppMopsArguments.c
===================================================================
--- trunk/ppTranslate/src/ppMopsArguments.c	(revision 34472)
+++ trunk/ppTranslate/src/ppMopsArguments.c	(revision 34473)
@@ -95,7 +95,7 @@
     psMetadataAddF32(arguments, PS_LIST_TAIL, "-astrom_rms", 0, "Astrometric solution RMS", NAN);
     psMetadataAddU16(arguments, PS_LIST_TAIL, "-version", 0, "CMF file version", 0);
-    psMetadataAddStr(arguments, PS_LIST_TAIL, "-comment", 0, "Exposure comment", NULL);
-    psMetadataAddStr(arguments, PS_LIST_TAIL, "-obsmode", 0, "Observation mode", NULL);
-    psMetadataAddStr(arguments, PS_LIST_TAIL, "-difftype", 0, "Either WW (Warp-Warp Diff) or WS (Warp-Stack Diff)", NULL);
+    psMetadataAddStr(arguments, PS_LIST_TAIL, "-comment", 0, "Exposure comment", "No comment provided");
+    psMetadataAddStr(arguments, PS_LIST_TAIL, "-obsmode", 0, "Observation mode", "No obsmode provided");
+    psMetadataAddStr(arguments, PS_LIST_TAIL, "-difftype", 0, "Either WW (Warp-Warp Diff) or WS (Warp-Stack Diff)", "No difftype provided");
     if (argc == 1 || !psArgumentParse(arguments, &argc, argv) || argc != 3) {
         usage(argv[0], arguments);