diff --git a/skimage/filter/rank/bilateral.py b/skimage/filter/rank/bilateral.py
index 834a24a8..6e11d6e5 100644
--- a/skimage/filter/rank/bilateral.py
+++ b/skimage/filter/rank/bilateral.py
@@ -22,8 +22,6 @@ References
 
 import numpy as np
 from skimage import img_as_ubyte
-from ... import get_log
-log = get_log()
 
 from . import bilateral_cy
 from .generic import _handle_input
diff --git a/skimage/filter/rank/generic.py b/skimage/filter/rank/generic.py
index e09bfba5..167d3aa0 100644
--- a/skimage/filter/rank/generic.py
+++ b/skimage/filter/rank/generic.py
@@ -55,6 +55,11 @@ def _handle_input(image, selem, out, mask):
     else:
         max_bin = max(4, image.max())
 
+    bitdepth = int(np.log2(max_bin))
+    if bitdepth > 10:
+        log.warn("Bitdepth of %d may result in bad rank filter "
+                 "performance due to large number of bins." % bitdepth)
+
     return image, selem, out, mask, max_bin
 
 
diff --git a/skimage/filter/rank/percentile.py b/skimage/filter/rank/percentile.py
index 3b0a04ba..10c4bb9e 100644
--- a/skimage/filter/rank/percentile.py
+++ b/skimage/filter/rank/percentile.py
@@ -22,9 +22,6 @@ References
 """
 
 import numpy as np
-from skimage import img_as_ubyte
-from ... import get_log
-log = get_log()
 
 from . import percentile_cy
 from .generic import _handle_input