Index: trunk/ppSim/src/ppSimArguments.c
===================================================================
--- trunk/ppSim/src/ppSimArguments.c	(revision 12973)
+++ trunk/ppSim/src/ppSimArguments.c	(revision 12975)
@@ -72,5 +72,5 @@
     psMetadataAddF32(arguments, PS_LIST_TAIL, "-starsmag", 0, "Brightest magnitude for fake stars", NAN);
     psMetadataAddF32(arguments, PS_LIST_TAIL, "-starsdensity", 0, "Density of fake stars at magnitude", NAN);
-    psMetadataAddS32(arguments, PS_LIST_TAIL, "-bin", 0, "Binning in x and y", 1);
+    psMetadataAddS32(arguments, PS_LIST_TAIL, "-bin", 1, "Binning in x and y", 1);
 
     if (!config->camera) {
@@ -166,10 +166,10 @@
                      "Overscan polynomial order", biasOrder);
 
-    int bin = psMetadataLookupS32(NULL, arguments, "-bin"); // Binning in x and y
-    if (bin <= 0) {
-        psError(PS_ERR_BAD_PARAMETER_VALUE, true, "Binning is non-positive.");
-        usage(arguments, config);
-    }
-    psMetadataAddS32(config->arguments, PS_LIST_TAIL, "BINNING", 0, "Binning in x and y", bin);
+    int binning = psMetadataLookupS32(NULL, arguments, "-bin"); // Binning in x and y
+    if (binning <= 0) {
+        psError(PS_ERR_BAD_PARAMETER_VALUE, true, "Binning (%d) is non-positive.", binning);
+        usage(arguments, config);
+    }
+    psMetadataAddS32(config->arguments, PS_LIST_TAIL, "BINNING", 0, "Binning in x and y", binning);
 
     psMetadataAddStr(config->arguments, PS_LIST_TAIL, "OUTPUT", 0, "Name of the output image",