Index: branches/pap/ppStack/src/ppStackThread.c
===================================================================
--- branches/pap/ppStack/src/ppStackThread.c	(revision 25780)
+++ branches/pap/ppStack/src/ppStackThread.c	(revision 25788)
@@ -56,5 +56,5 @@
 }
 
-ppStackThreadData *ppStackThreadDataSetup(const ppStackOptions *options, const pmConfig *config)
+ppStackThreadData *ppStackThreadDataSetup(const ppStackOptions *options, const pmConfig *config, bool conv)
 {
     psAssert(options, "Require options");
@@ -62,14 +62,16 @@
 
     const psArray *cells = options->cells; // Array of input cells
-    const psArray *imageNames = options->imageNames; // Names of images to read
-    const psArray *maskNames = options->maskNames; // Names of masks to read
-    const psArray *varianceNames = options->varianceNames; // Names of variance maps to read
-    const psArray *covariances = options->covariances; // Covariance matrices (already read)
+    const psArray *imageNames = conv ? options->convImages : options->origImages; // Names of images to read
+    const psArray *maskNames = conv ? options->convMasks : NULL; // Names of masks to read
+    const psArray *varianceNames = conv ? options->convVariances : NULL; // Names of variance maps to read
+    const psArray *covariances = conv ? options->covariances : NULL; // Covariance matrices (already read)
 
     PS_ASSERT_ARRAY_NON_NULL(cells, NULL);
     PS_ASSERT_ARRAYS_SIZE_EQUAL(cells, imageNames, NULL);
-    PS_ASSERT_ARRAYS_SIZE_EQUAL(cells, maskNames, NULL);
-    PS_ASSERT_ARRAYS_SIZE_EQUAL(cells, varianceNames, NULL);
-    PS_ASSERT_ARRAYS_SIZE_EQUAL(cells, covariances, NULL);
+    if (conv) {
+        PS_ASSERT_ARRAYS_SIZE_EQUAL(cells, maskNames, NULL);
+        PS_ASSERT_ARRAYS_SIZE_EQUAL(cells, varianceNames, NULL);
+        PS_ASSERT_ARRAYS_SIZE_EQUAL(cells, covariances, NULL);
+    }
 
     ppStackThreadData *stack = psAlloc(sizeof(ppStackThreadData)); // Thread data, to return
@@ -87,19 +89,21 @@
             continue;
         }
-        // Resolved names
-        psString imageResolved = pmConfigConvertFilename(imageNames->data[i], config, false, false);
-        psString maskResolved = pmConfigConvertFilename(maskNames->data[i], config, false, false);
-        psString varianceResolved = pmConfigConvertFilename(varianceNames->data[i], config, false, false);
-        stack->imageFits->data[i] = psFitsOpen(imageResolved, "r");
-        stack->maskFits->data[i] = psFitsOpen(maskResolved, "r");
-        stack->varianceFits->data[i] = psFitsOpen(varianceResolved, "r");
-        psFree(imageResolved);
-        psFree(maskResolved);
-        psFree(varianceResolved);
-        if (!stack->imageFits->data[i] || !stack->maskFits->data[i] || !stack->varianceFits->data[i]) {
-            psError(PS_ERR_UNKNOWN, false, "Unable to open convolved files %s, %s, %s",
-                    (char*)imageNames->data[i], (char*)maskNames->data[i], (char*)varianceNames->data[i]);
-            return NULL;
-        }
+
+// Open an image
+#define IMAGE_OPEN(NAME, FITS) \
+        if (NAME) { \
+            psString resolved = pmConfigConvertFilename(NAME, config, false, false); \
+            FITS = psFitsOpen(resolved, "r"); \
+            if (!(FITS)) { \
+                psError(PS_ERR_IO, false, "Unable to open file %s", (char*)(NAME)); \
+                psFree(resolved); \
+                return NULL; \
+            } \
+            psFree(resolved); \
+        }
+
+        IMAGE_OPEN(imageNames->data[i], stack->imageFits->data[i]);
+        IMAGE_OPEN(maskNames->data[i], stack->maskFits->data[i]);
+        IMAGE_OPEN(varianceNames->data[i], stack->varianceFits->data[i]);
     }
 
@@ -116,5 +120,7 @@
             }
             pmReadout *ro = pmReadoutAlloc(cell); // Readout for thread
-            ro->covariance = psMemIncrRefCounter(covariances->data[j]);
+            if (conv) {
+                ro->covariance = psMemIncrRefCounter(covariances->data[j]);
+            }
             readouts->data[j] = ro;
         }
@@ -187,7 +193,8 @@
 
 
-		int zMax = 0;
+                int zMax = 0;
                 bool keepReading = false;
-                if (pmReadoutMore(ro, imageFits, 0, &zMax, rows, config)) {
+
+                if (imageFits && pmReadoutMore(ro, imageFits, 0, &zMax, rows, config)) {
                     keepReading = true;
                     if (!pmReadoutReadChunk(ro, imageFits, 0, NULL, rows, overlap, config)) {
@@ -199,5 +206,5 @@
                 }
 
-                if (pmReadoutMoreMask(ro, maskFits, 0, &zMax, rows, config)) {
+                if (maskFits && pmReadoutMoreMask(ro, maskFits, 0, &zMax, rows, config)) {
                     keepReading = true;
                     if (!pmReadoutReadChunkMask(ro, maskFits, 0, NULL, rows, overlap, config)) {
@@ -209,5 +216,5 @@
                 }
 
-                if (pmReadoutMoreVariance(ro, varianceFits, 0, &zMax, rows, config)) {
+                if (varianceFits && pmReadoutMoreVariance(ro, varianceFits, 0, &zMax, rows, config)) {
                     keepReading = true;
                     if (!pmReadoutReadChunkVariance(ro, varianceFits, 0, NULL, rows, overlap, config)) {