Index: trunk/psModules/src/detrend/pmRemnance.c
===================================================================
--- trunk/psModules/src/detrend/pmRemnance.c	(revision 20622)
+++ trunk/psModules/src/detrend/pmRemnance.c	(revision 20624)
@@ -72,12 +72,14 @@
         }
 
-        maxMask += size;
-        if (maxMask > numRows) {
-            maxMask = numRows;
+        if (maxMask > 0) {
+            maxMask += size;
+            if (maxMask > numRows) {
+                maxMask = numRows;
+            }
+            for (int y = 0; y < maxMask; y++) {
+                mask->data.PS_TYPE_MASK_DATA[y][x] |= maskRem;
+            }
+            numMasked += maxMask;
         }
-        for (int y = 0; y < maxMask; y++) {
-            mask->data.PS_TYPE_MASK_DATA[y][x] |= maskRem;
-        }
-        numMasked += maxMask;
 
     }