Index: trunk/ppSub/src/ppSubDefineOutput.c
===================================================================
--- trunk/ppSub/src/ppSubDefineOutput.c	(revision 23403)
+++ trunk/ppSub/src/ppSubDefineOutput.c	(revision 23740)
@@ -21,25 +21,29 @@
 #include "ppSub.h"
 
-bool ppSubDefineOutput(pmConfig *config, const pmFPAview *view)
+bool ppSubDefineOutput(const char *name, pmConfig *config)
 {
+    psAssert(name, "Require name");
     psAssert(config, "Require configuration");
-    psAssert(view, "Require view");
 
-    pmCell *outCell = pmFPAfileThisCell(config->files, view, "PPSUB.OUTPUT"); // Output cell
+    pmFPAview *view = ppSubViewReadout(); // View to readout
+    pmCell *outCell = pmFPAfileThisCell(config->files, view, name); // Output cell
     pmFPA *outFPA = outCell->parent->parent; // Output FPA
-    pmHDU *outHDU = outFPA->hdu; // Output HDU
+    pmHDU *outHDU = outFPA->hdu;        // Output HDU
     if (!outHDU->header) {
         outHDU->header = psMetadataAlloc();
     }
 
-    // generate an output readout (first check if it's already there by virtue of kernels)
-    pmReadout *outRO = pmFPAfileThisReadout(config->files, view, "PPSUB.OUTPUT.KERNELS"); // RO with kernel
-    if (!outRO) {
-        outRO = pmReadoutAlloc(outCell); // Output readout: subtraction
+    // The output readout may already be present if we read in the convolution kernel
+    pmReadout *outRO = NULL;            // Output readout
+    if (outCell->readouts && outCell->readouts->n > 0 && outCell->readouts->data[0]) {
+        outRO = psMemIncrRefCounter(outCell->readouts->data[0]);
+    } else {
+        outRO = pmReadoutAlloc(outCell);
     }
 
-    // convolved input images
+    // Convolved input images
     pmReadout *inConv = pmFPAfileThisReadout(config->files, view, "PPSUB.INPUT.CONV"); // Input readout
     pmReadout *refConv = pmFPAfileThisReadout(config->files, view, "PPSUB.REF.CONV"); // Reference readout
+    psFree(view);
 
     // Add kernel descrption to header.
@@ -55,6 +59,4 @@
     if (!kernels) {
         psError(PS_ERR_UNEXPECTED_NULL, true, "Unable to find SUBTRACTION.KERNEL");
-        psFree(inConv);
-        psFree(refConv);
         psFree(outRO);
         return false;
@@ -63,15 +65,17 @@
                      kernels->description);
 
+    // Add additional data to the header
+    pmFPAfile *refFile = psMetadataLookupPtr(NULL, config->files, "PPSUB.REF"); // Reference file
+    pmFPAfile *inFile = psMetadataLookupPtr(NULL, config->files, "PPSUB.INPUT"); // Input file
+    psMetadataAddStr(outHDU->header, PS_LIST_TAIL, "PPSUB.REFERENCE", 0,
+                     "Subtraction reference", refFile->filename);
+    psMetadataAddStr(outHDU->header, PS_LIST_TAIL, "PPSUB.INPUT", 0,
+                     "Subtraction input", inFile->filename);
+    ppSubVersionHeader(outHDU->header);
+
+
     outRO->analysis = psMetadataCopy(outRO->analysis, analysis);
 
-#ifdef TESTING
-    {
-        psImage *kernelImage = psMetadataLookupPtr(&mdok, analysis,
-                                                   "SUBTRACTION.KERNEL.IMAGE"); // Image of kernel
-        psFits *fits = psFitsOpen("kernel.fits", "w");
-        psFitsWriteImage(fits, NULL, kernelImage, 0, NULL);
-        psFitsClose(fits);
-    }
-#endif
+    psFree(outRO);
 
     return true;