Index: /branches/eam_branches/ipp-20101205/ippconfig/recipes/ppSub.config
===================================================================
--- /branches/eam_branches/ipp-20101205/ippconfig/recipes/ppSub.config	(revision 30398)
+++ /branches/eam_branches/ipp-20101205/ippconfig/recipes/ppSub.config	(revision 30399)
@@ -32,4 +32,6 @@
 INPUT.MATCH.MIN.SN F32  10.0
 
+ADD.NOT.SUBTRACT BOOL   FALSE           # add the images instead of subtracting (ie, image + ref, not image - ref)
+
 LOW.THRESHOLD	F32	20.0	        # Mask pixels below this threshold (std dev)
 POOR.FRACTION	F32	0.20		# Maximum fraction of bad weight for poor pixels