Index: /trunk/psModules/src/imcombine/pmSubtractionKernels.c
===================================================================
--- /trunk/psModules/src/imcombine/pmSubtractionKernels.c	(revision 15428)
+++ /trunk/psModules/src/imcombine/pmSubtractionKernels.c	(revision 15429)
@@ -572,5 +572,6 @@
                     for (int v = -size; v <= size; v++) {
                         int v2 = PS_SQR(v);   // Square of v
-                        float vPoly = power(v, vOrder); // Value of v^vOrder
+//                        float vPoly = power(v, vOrder); // Value of v^vOrder
+                        float vPoly = powf(v/(float)size, vOrder); // Value of v^vOrder
 
                         for (int u = -size; u <= size; u++) {
@@ -578,5 +579,6 @@
                             int distance2 = u2 + v2; // Distance from the centre
                             if (distance2 > lower2 && distance2 < upper2) {
-                                float uPoly = power(u, uOrder); // Value of u^uOrder
+//                                float uPoly = power(u, uOrder); // Value of u^uOrder
+                                float uPoly = powf(u/(float)size, uOrder); // Value of u^uOrder
 
                                 float polyVal = uPoly * vPoly; // Value of polynomial