diff --git a/include/vision.h b/include/vision.h
index 7d1f651b6..988496a31 100644
--- a/include/vision.h
+++ b/include/vision.h
@@ -52,7 +52,7 @@
 /*
  *  Circle information
  */
-#define MAX_RADIUS 16 /* this is in points from the source */
+#define MAX_RADIUS 15 /* this is in points from the source */
 
 /* Use this macro to get a list of distances of the edges (see vision.c). */
 #define circle_ptr(z) (&circle_data[(int) circle_start[z]])