diff --git a/bioem_algorithm.h b/bioem_algorithm.h
index c1936efe85e6e38998f7c1f5b4caf566fec361df..21fc16a42bcdf835586a8bda82dcba4e0eb3f3f5 100644
--- a/bioem_algorithm.h
+++ b/bioem_algorithm.h
@@ -174,7 +174,7 @@ __device__ static inline void doRefMapFFT(const int iRefMap, const int iOrient,
 
   for (int cent_x = param.NumberPixels - param.maxDisplaceCenter; cent_x < param.NumberPixels; cent_x = cent_x + param.GridSpaceCenter)
     {
-      for (int cent_y = 0; cent_y < param.maxDisplaceCenter; cent_y = cent_y + param.GridSpaceCenter)
+      for (int cent_y = 0; cent_y <= param.maxDisplaceCenter; cent_y = cent_y + param.GridSpaceCenter)
 	{
 	  calProb(iRefMap, iOrient, iConv,amp, pha, env, sumC, sumsquareC, (myfloat_t) lCC[cent_x * param.NumberPixels + cent_y] / (myfloat_t) (param.NumberPixels * param.NumberPixels), cent_x - param.NumberPixels, cent_y, pProb, param, RefMap);
 	}