Index: trunk/ppSim/src/ppSimInsertStars.c
===================================================================
--- trunk/ppSim/src/ppSimInsertStars.c	(revision 28125)
+++ trunk/ppSim/src/ppSimInsertStars.c	(revision 28127)
@@ -108,5 +108,5 @@
 	// in this case, simply place delta functions in the image
 	if (psfConvolve) {
-	    readout->image->data.F32[(int)(yCell)][(int)(xCell)] = flux;
+	    readout->image->data.F32[(int)(yCell)][(int)(xCell)] += flux;
 	    continue;
 	}