Index: trunk/psModules/src/imcombine/pmSubtraction.c
===================================================================
--- trunk/psModules/src/imcombine/pmSubtraction.c	(revision 19535)
+++ trunk/psModules/src/imcombine/pmSubtraction.c	(revision 19540)
@@ -586,12 +586,16 @@
           psVector *poly = preCalc->data[2]; // Polynomial values
           int num = uCoords->n;         // Number of pixels
+          psS32 *uData = uCoords->data.S32, *vData = vCoords->data.S32; // Dereference u,v coordinates
+          psF32 *polyData = poly->data.F32; // Dereference polynomial values
+          psF32 **imageData = image->kernel;  // Dereference image
+          psF32 **convData = convolved->kernel; // Dereference convolved image
           for (int y = -footprint; y <= footprint; y++) {
               for (int x = -footprint; x <= footprint; x++) {
                   double sum = 0.0;             // Accumulated sum from convolution
                   for (int j = 0; j < num; j++) {
-                      int u = uCoords->data.S32[j], v = vCoords->data.S32[j]; // Kernel coordinates
-                      sum += image->kernel[y - v][x - u] * poly->data.F32[j];
+                      int u = uData[j], v = vData[j]; // Kernel coordinates
+                      sum += imageData[y - v][x - u] * polyData[j];
                   }
-                  convolved->kernel[y][x] = sum;
+                  convData[y][x] = sum;
                   // Photometric scaling is built into the kernel --- no subtraction!
               }