Index: trunk/psphot/src/psphotMergeSources.c
===================================================================
--- trunk/psphot/src/psphotMergeSources.c	(revision 20356)
+++ trunk/psphot/src/psphotMergeSources.c	(revision 21176)
@@ -100,6 +100,11 @@
         peak->xf = xpos;
         peak->yf = ypos;
-        peak->flux = flux;
-        peak->SN = snMin + flux;
+        peak->flux = flux; // this are being set wrong, but does it matter?
+
+	if (isfinite (source->errMag) && (source->errMag > 0.0)) {
+	  peak->SN = 1.0 / source->errMag; 
+	} else {
+	  peak->SN = 0.0;
+	}
 
         psArrayAdd (detections->peaks, 100, peak);