Index: trunk/ppSub/src/ppSubVarianceRescale.c
===================================================================
--- trunk/ppSub/src/ppSubVarianceRescale.c	(revision 27317)
+++ trunk/ppSub/src/ppSubVarianceRescale.c	(revision 28121)
@@ -22,5 +22,5 @@
 #include "ppSub.h"
 
-bool ppSubVarianceRescale(pmConfig *config)
+bool ppSubVarianceRescale(pmConfig *config, ppSubData *data)
 {
     psAssert(config, "Require configuration");
@@ -60,4 +60,13 @@
     }
 
-    return pmReadoutVarianceRenormalise(readout, maskBad, num, minValid, maxValid);
+    if (!pmReadoutVarianceRenormalise(readout, maskBad, num, minValid, maxValid)) {
+        psErrorStackPrint(stderr, "Unable to renormalise variances");
+        psWarning("Unable to renormalise variances --- suspect bad data quality.");
+        // Allow the convolved and subtracted images to be written
+        ppSubDataQuality(data, PPSUB_ERR_VARIANCE,
+                         PPSUB_FILES_INPUT | PPSUB_FILES_PHOT_SUB | PPSUB_FILES_PHOT_INV |
+                         PPSUB_FILES_PSF | PPSUB_FILES_PHOT);
+    }
+
+    return true;
 }