Index: trunk/ppSub/src/ppSubConvolve.c
===================================================================
--- trunk/ppSub/src/ppSubConvolve.c	(revision 28567)
+++ trunk/ppSub/src/ppSubConvolve.c	(revision 29551)
@@ -241,4 +241,15 @@
             psThreadPoolInit(threads);
         }
+
+	// Mask the NAN values (USE BLANK instead of SAT?)
+	if (!pmReadoutMaskInvalid(input, maskVal, maskBad)) {
+	  psError(PPSUB_ERR_DATA, false, "Unable to mask non-finite pixels in input.");
+	  return false;
+	}
+	if (!pmReadoutMaskInvalid(ref, maskVal, maskBad)) {
+	  psError(PPSUB_ERR_DATA, false, "Unable to mask non-finite pixels in reference.");
+	  return false;
+	}
+
         if (!pmSubtractionMatchPrecalc(inConv, refConv, input, ref, inRO->analysis,
                                        stride, kernelErr, covarFrac, maskVal, maskBad, maskPoor,