Index: trunk/ppStack/src/ppStackCombinePrepare.c
===================================================================
--- trunk/ppStack/src/ppStackCombinePrepare.c	(revision 27400)
+++ trunk/ppStack/src/ppStackCombinePrepare.c	(revision 27402)
@@ -10,6 +10,5 @@
 #include "ppStackLoop.h"
 
-bool ppStackCombinePrepare(const char *outName, const char *expName,
-                           ppStackFileList files, ppStackThreadData *stack,
+bool ppStackCombinePrepare(pmReadout **ro, const char *name, ppStackFileList files, ppStackThreadData *stack,
                            ppStackOptions *options, pmConfig *config)
 {
@@ -33,9 +32,6 @@
     }
 
-    pmCell *cell = pmFPAfileThisCell(config->files, view, outName); // Output cell
-    options->outRO = pmReadoutAlloc(cell); // Output readout
-
-    pmCell *expCell = pmFPAfileThisCell(config->files, view, expName); // Exposure cell
-    options->expRO = pmReadoutAlloc(expCell); // Output readout
+    pmCell *cell = pmFPAfileThisCell(config->files, view, name); // Output cell
+    *ro = pmReadoutAlloc(cell); // Output readout
 
     psFree(view);
@@ -46,10 +42,5 @@
     psImageMaskType maskBad = pmConfigMaskGet(maskBadStr, config); // Bits to mask for bad pixels
 
-    if (!pmReadoutStackDefineOutput(options->outRO, col0, row0, numCols, numRows, true, true, maskBad)) {
-        psError(PPSTACK_ERR_ARGUMENTS, false, "Unable to prepare output.");
-        return false;
-    }
-
-    if (!pmReadoutStackDefineOutput(options->expRO, col0, row0, numCols, numRows, true, true, 0)) {
+    if (!pmReadoutStackDefineOutput(*ro, col0, row0, numCols, numRows, true, true, maskBad)) {
         psError(PPSTACK_ERR_ARGUMENTS, false, "Unable to prepare output.");
         return false;