Index: trunk/ppImage/src/ppImageReplaceBackground.c
===================================================================
--- trunk/ppImage/src/ppImageReplaceBackground.c	(revision 23287)
+++ trunk/ppImage/src/ppImageReplaceBackground.c	(revision 23825)
@@ -147,5 +147,5 @@
             if (!isfinite(value)) {
                 image->data.F32[y][x] = NAN;
-                mask->data.PS_TYPE_IMAGE_MASK_DATA[y][x] |= options->badMask;
+                mask->data.PS_TYPE_IMAGE_MASK_DATA[y][x] |= options->lowMask;
             } else {
                 image->data.F32[y][x] -= value;
@@ -164,5 +164,5 @@
                 if (!isfinite(value)) {
                     image->data.F32[y][x] = NAN;
-                    mask->data.PS_TYPE_IMAGE_MASK_DATA[y][x] |= options->badMask;
+                    mask->data.PS_TYPE_IMAGE_MASK_DATA[y][x] |= options->lowMask;
                 } else {
                     image->data.F32[y][x] -= value;