Index: trunk/ppStack/src/ppStackSources.c
===================================================================
--- trunk/ppStack/src/ppStackSources.c	(revision 23211)
+++ trunk/ppStack/src/ppStackSources.c	(revision 23212)
@@ -81,12 +81,19 @@
 
     float radius = psMetadataLookupF32(NULL, recipe, "ZP.RADIUS"); // Radius (pixels) for matching sources
-    int iter = psMetadataLookupS32(NULL, recipe, "ZP.ITER"); // Maximum iterations
+    int iter1 = psMetadataLookupS32(NULL, recipe, "ZP.ITER.1"); // Maximum iterations for pass 1
+    int iter2 = psMetadataLookupS32(NULL, recipe, "ZP.ITER.2"); // Maximum iterations for pass 2
     float tol = psMetadataLookupF32(NULL, recipe, "ZP.TOL"); // Tolerance for zero point iterations
     int transIter = psMetadataLookupS32(NULL, recipe, "ZP.TRANS.ITER"); // Iterations for transparency
     float transRej = psMetadataLookupF32(NULL, recipe, "ZP.TRANS.REJ");// Rejection threshold for transparency
     float transThresh = psMetadataLookupF32(NULL, recipe, "ZP.TRANS.THRESH"); // Threshold for transparency
-    float starRej = psMetadataLookupF32(NULL, recipe, "ZP.STAR.REJ"); // Rejection threshold for stars
+
+    float starRej1 = psMetadataLookupF32(NULL, recipe, "ZP.STAR.REJ.1"); // Rejection threshold for stars
+    float starSys1 = psMetadataLookupF32(NULL, recipe, "ZP.STAR.SYS.1"); // Estimated systematic error
+    float starRej2 = psMetadataLookupF32(NULL, recipe, "ZP.STAR.REJ.2"); // Rejection threshold for stars
+    float starSys2 = psMetadataLookupF32(NULL, recipe, "ZP.STAR.SYS.2"); // Estimated systematic error
+
     float starLimit = psMetadataLookupF32(NULL, recipe, "ZP.STAR.LIMIT"); // Limit on star rejection fraction
-    float starSys = psMetadataLookupF32(NULL, recipe, "ZP.STAR.SYS"); // Estimated systematic error
+
+    float fracMatch = psMetadataLookupF32(NULL, recipe, "ZP.MATCH"); // Fraction of images to match for star
 
     psMetadata *airmassZP = psMetadataLookupMetadata(NULL, recipe, "ZP.AIRMASS"); // Airmass terms
@@ -164,6 +171,7 @@
 #endif
 
-    psVector *trans = pmSourceMatchRelphot(matches, zp, iter, tol, starLimit, transIter, transRej,
-                                           transThresh, starRej, starSys); // Transparencies for each image
+    psVector *trans = pmSourceMatchRelphot(matches, zp, tol, iter1, starRej1, starSys1,
+                                           iter2, starRej2, starSys2, starLimit,
+                                           transIter, transRej, transThresh); // Transparencies for each image
     if (!trans) {
         psError(PS_ERR_UNKNOWN, false, "Unable to measure transparencies");
@@ -184,8 +192,8 @@
     // XXX this is a really poor output location; clean up the pmFPAfiles used in ppStack
     pmCell *sourcesCell = pmFPAfileThisCell(config->files, view, "PPSTACK.OUTPUT");
-    psArray *sourcesBest = psArrayAllocEmpty (100);
-
-    // XXX something of a hack: require at least 2 detections or 1/2 of the max possible
-    int minMatches = PS_MAX(2, 0.3*num);// Minimum number of matches required
+    psArray *sourcesBest = psArrayAllocEmpty(matches->n);
+
+    // XXX something of a hack: require at least 2 detections or the nominated fraction of the max possible
+    int minMatches = PS_MAX(2, fracMatch * num);// Minimum number of matches required
     for (int i = 0; i < matches->n; i++) {
         pmSourceMatch *match = matches->data[i]; // Match of interest
@@ -200,5 +208,5 @@
         pmSource *source = sources->data[index]; // Source of interest
 
-        psArrayAdd(sourcesBest, 100, source);
+        psArrayAdd(sourcesBest, sourcesBest->n, source);
     }
     psMetadataAdd(sourcesCell->analysis, PS_LIST_TAIL, "PSPHOT.SOURCES", PS_DATA_ARRAY | PS_META_REPLACE,