Index: trunk/ppSub/src/ppSubArguments.c
===================================================================
--- trunk/ppSub/src/ppSubArguments.c	(revision 13368)
+++ trunk/ppSub/src/ppSubArguments.c	(revision 13369)
@@ -17,5 +17,5 @@
 {
     fprintf(stderr, "\nPan-STARRS PSF-matched image subtraction\n\n");
-    fprintf(stderr, "Usage: %s INPUT.fits REFERENCE.fits OUTPUT.fits\n", program);
+    fprintf(stderr, "Usage: %s INPUT.fits REFERENCE.fits OUTPUT_ROOT\n", program);
     fprintf(stderr, "\n");
     psArgumentHelp(arguments);