Index: trunk/psphot/src/psphotSignificanceImage.c
===================================================================
--- trunk/psphot/src/psphotSignificanceImage.c	(revision 21407)
+++ trunk/psphot/src/psphotSignificanceImage.c	(revision 25383)
@@ -22,20 +22,23 @@
     }
 
-    bool status_x, status_y;
-    float FWHM_X = psMetadataLookupF32 (&status_x, recipe, "FWHM_X");
-    float FWHM_Y = psMetadataLookupF32 (&status_y, recipe, "FWHM_Y");
-    if (status_x && status_y) {
-      // if we know the FHWM, use that to set the smoothing kernel (XXX allow an optional override?)
-      SIGMA_SMTH  = 0.5*(FWHM_X + FWHM_Y) / (2.0*sqrt(2.0*log(2.0)));
-      NSIGMA_SMTH = psMetadataLookupF32 (&status, recipe, "PEAKS_SMOOTH_NSIGMA");
-      guess = false;
+    bool statusMajor, statusMinor;
+    float fwhmMajor = psMetadataLookupF32(&statusMajor, recipe, "FWHM_MAJ");
+    float fwhmMinor = psMetadataLookupF32(&statusMinor, recipe, "FWHM_MIN");
+    if (statusMajor && statusMinor) {
+        // if we know the FHWM, use that to set the smoothing kernel (XXX allow an optional override?)
+        if (!isfinite(fwhmMajor) || !isfinite(fwhmMinor) || fwhmMajor == 0.0 || fwhmMinor == 0.0) {
+            psWarning("fwhmMajor (%f) or fwhmMinor (%f) is bad!", fwhmMajor, fwhmMinor);
+        }
+        SIGMA_SMTH  = 0.5*(fwhmMajor + fwhmMinor) / (2.0*sqrt(2.0*log(2.0)));
+        NSIGMA_SMTH = psMetadataLookupF32 (&status, recipe, "PEAKS_SMOOTH_NSIGMA");
+        guess = false;
     } else {
-      // if we do not know the FWHM, use the guess smoothing kernel supplied.
-      // it is a configuration error if these are not supplied
-      SIGMA_SMTH  = psMetadataLookupF32 (&status, recipe, "PEAKS_SMOOTH_SIGMA");
-      PS_ASSERT (status, NULL);
-      NSIGMA_SMTH = psMetadataLookupF32 (&status, recipe, "PEAKS_SMOOTH_NSIGMA");
-      PS_ASSERT (status, NULL);
-      guess = true;
+        // if we do not know the FWHM, use the guess smoothing kernel supplied.
+        // it is a configuration error if these are not supplied
+        SIGMA_SMTH  = psMetadataLookupF32 (&status, recipe, "PEAKS_SMOOTH_SIGMA");
+        PS_ASSERT (status, NULL);
+        NSIGMA_SMTH = psMetadataLookupF32 (&status, recipe, "PEAKS_SMOOTH_NSIGMA");
+        PS_ASSERT (status, NULL);
+        guess = true;
     }
     // record the actual smoothing sigma
