diff --git a/skimage/rank/tests/demo_single.py b/skimage/rank/tests/demo_single.py
index 7ff12b28..96f1fbeb 100644
--- a/skimage/rank/tests/demo_single.py
+++ b/skimage/rank/tests/demo_single.py
@@ -9,11 +9,12 @@ import skimage.rank as rank
 
 if __name__ == '__main__':
     a8 = data.camera()
-    a16 = data.camera().astype(np.uint16)
+    a16 = data.camera().astype(np.uint16)*4
     selem = disk(10)
 
     f8= rank.percentile_autolevel(a8,selem,p0=.0,p1=1.)
     f16= rank.autolevel(a16,selem)
+    f16p= rank.percentile_autolevel(a16,selem,p0=.0,p1=1.)
 
     print f8==f16
 
@@ -21,7 +22,7 @@ if __name__ == '__main__':
     plt.subplot(1,2,1)
     plt.imshow(f16)
     plt.subplot(1,2,2)
-    plt.imshow(f8)
+    plt.imshow(f16p-f16)
     plt.show()
 
 
diff --git a/skimage/rank/tests/test_suite.py b/skimage/rank/tests/test_suite.py
index e7d2436b..9ed39956 100644
--- a/skimage/rank/tests/test_suite.py
+++ b/skimage/rank/tests/test_suite.py
@@ -105,7 +105,7 @@ class TestSequenceFunctions(unittest.TestCase):
         assert (loc_autolevel==loc_perc_autolevel).all()
 
     def test_compare_autolevels_16bit(self):
-        image = data.camera().astype(np.uint16)
+        image = data.camera().astype(np.uint16)*4
 
         selem = disk(20)
         loc_autolevel = rank.autolevel(image,selem=selem)