Index: trunk/psModules/src/camera/pmFPAMosaic.c
===================================================================
--- trunk/psModules/src/camera/pmFPAMosaic.c	(revision 10966)
+++ trunk/psModules/src/camera/pmFPAMosaic.c	(revision 11255)
@@ -1200,5 +1200,10 @@
         return false;
     }
-    targetHDU->header = psMetadataCopy(targetHDU->header, sourceHDU->header);
+
+    if (sourceHDU->header) {
+        targetHDU->header = psMetadataCopy(targetHDU->header, sourceHDU->header);
+    } else if (!targetHDU->header) {
+        targetHDU->header = psMetadataAlloc();
+    }
 
     if (!pmConfigConformHeader(targetHDU->header, targetHDU->format)) {