Index: trunk/ppImage/src/ppImageMosaic.c
===================================================================
--- trunk/ppImage/src/ppImageMosaic.c	(revision 10214)
+++ trunk/ppImage/src/ppImageMosaic.c	(revision 10589)
@@ -21,7 +21,9 @@
     }
 
-    pmFPAAddSourceFromView(out->fpa, view, out->format);
     pmChip *outChip = pmFPAviewThisChip(view, out->fpa);
     pmChip *inChip = pmFPAviewThisChip(view, in->fpa);
+    if (!outChip->hdu && !outChip->parent->hdu) {
+        pmFPAAddSourceFromView(out->fpa, view, out->format);
+    }
 
     // Copy over concepts