diff --git a/findmaxima2d/cfindmaxima2d.pyx b/findmaxima2d/cfindmaxima2d.pyx
index f6f1556..1f7e2fd 100644
--- a/findmaxima2d/cfindmaxima2d.pyx
+++ b/findmaxima2d/cfindmaxima2d.pyx
@@ -207,9 +207,9 @@ def find_maxima(img_data_py,local_max_py,ntol_py):
 			#   types[pListy[0:listlen],pListx[0:listlen]] =0
 			#else:
 			if maxPossible == 1:
-				resetMask = ~(LISTED)
+				resetMask = ~(LISTED) & 0xFF
 			else:
-				resetMask = ~(LISTED|EQUAL)
+				resetMask = ~(LISTED|EQUAL) & 0xFF
 
 			#Now we calculate the x and y-coordinates, if there were any equal.
 			xEqual /= nEqual
diff --git a/findmaxima2d/findmaxima2d.pyx b/findmaxima2d/findmaxima2d.pyx
index 4051db3..bdd8414 100644
--- a/findmaxima2d/findmaxima2d.pyx
+++ b/findmaxima2d/findmaxima2d.pyx
@@ -207,9 +207,9 @@ def find_maxima(img_data_py,local_max_py,ntol_py):
 			#   types[pListy[0:listlen],pListx[0:listlen]] =0
 			#else:
 			if maxPossible == 1:
-				resetMask = ~(LISTED)
+				resetMask = ~(LISTED) & 0xFF
 			else:
-				resetMask = ~(LISTED|EQUAL)
+				resetMask = ~(LISTED|EQUAL) & 0xFF
 
 			#Now we calculate the x and y-coordinates, if there were any equal.
 			xEqual /= nEqual