Index: trunk/psModules/src/imcombine/pmSubtractionStamps.c
===================================================================
--- trunk/psModules/src/imcombine/pmSubtractionStamps.c	(revision 19201)
+++ trunk/psModules/src/imcombine/pmSubtractionStamps.c	(revision 19202)
@@ -27,4 +27,6 @@
 #define SOURCE_MASK (PM_SOURCE_MODE_CR_LIMIT | PM_SOURCE_MODE_SATURATED | PM_SOURCE_MODE_DEFECT | \
                      PM_SOURCE_MODE_SATSTAR | PM_SOURCE_MODE_FAIL) // Mask for bad sources
+#define SOURCE_FAINTEST 50.0            // Faintest magnitude to consider
+
 
 //////////////////////////////////////////////////////////////////////////////////////////////////////////////
@@ -594,5 +596,6 @@
     for (int i = 0; i < numSources; i++) {
         pmSource *source = sources->data[i]; // Source of interest
-        if (source->mode & SOURCE_MASK) {
+        if (!source || (source->mode & SOURCE_MASK) || !isfinite(source->psfMag) ||
+            source->psfMag > SOURCE_FAINTEST) {
             continue;
         }