Index: trunk/psphot/src/psphotDefineFiles.c
===================================================================
--- trunk/psphot/src/psphotDefineFiles.c	(revision 12805)
+++ trunk/psphot/src/psphotDefineFiles.c	(revision 13008)
@@ -40,4 +40,13 @@
 	if (!pmFPAfileDefineFromFPA (config, input->fpa, DX, DY, "PSPHOT.BACKMDL")) {
 	    psError(PSPHOT_ERR_CONFIG, false, "Cannot find a rule for PSPHOT.BACKMDL");
+	    return false;
+	}
+    }
+    // optionally save the background model's standard deviation (small FITS image)
+    if (psMetadataLookupBool(NULL, recipe, "SAVE.BACKMDL.STDEV")) {
+	int DX = psMetadataLookupS32 (&status, recipe, "BACKGROUND.XBIN");
+	int DY = psMetadataLookupS32 (&status, recipe, "BACKGROUND.YBIN");
+	if (!pmFPAfileDefineFromFPA (config, input->fpa, DX, DY, "PSPHOT.BACKMDL.STDEV")) {
+	    psError(PSPHOT_ERR_CONFIG, false, "Cannot find a rule for PSPHOT.BACKMDL.STDEV");
 	    return false;
 	}