Index: /branches/eam_branches/ipp-20110505/psphot/src/psphotSkyReplace.c
===================================================================
--- /branches/eam_branches/ipp-20110505/psphot/src/psphotSkyReplace.c	(revision 31608)
+++ /branches/eam_branches/ipp-20110505/psphot/src/psphotSkyReplace.c	(revision 31609)
@@ -41,5 +41,5 @@
     // select the corresponding images
     psF32 **image = readout->image->data.F32;
-    psImageMaskType  **mask  = readout->mask->data.PS_TYPE_IMAGE_MASK_DATA;
+    // psImageMaskType  **mask  = readout->mask->data.PS_TYPE_IMAGE_MASK_DATA;
     psF32 **back  = background->image->data.F32;
 
@@ -47,5 +47,5 @@
     for (int j = 0; j < readout->image->numRows; j++) {
         for (int i = 0; i < readout->image->numCols; i++) {
-            if (!mask[j][i]) {
+            if (isfinite(image[j][i]) && isfinite(back[j][i])) {
                 image[j][i] += back[j][i];
             }