diff --git a/python/cextern/fast_median/fast_median.py b/python/cextern/fast_median/fast_median.py
index d9362c80..482e5517 100644
--- a/python/cextern/fast_median/fast_median.py
+++ b/python/cextern/fast_median/fast_median.py
@@ -35,7 +35,7 @@
                                         ndpointer(ctypes.c_double, flags="C_CONTIGUOUS"))
     lib.median_filter_2d_double.restype = None
 
-    lib.median_filter_1d_float.argtypes = (ctypes.c_int, 
+    lib.median_filter_1d_float.argtypes = (ctypes.c_int,
                                         ctypes.c_int,
                                         ctypes.c_int,
                                         ndpointer(ctypes.c_float, flags="C_CONTIGUOUS"),
@@ -81,6 +81,6 @@ def fast_median_filter_1d(input, size=None):
         return out
 else:
     def fast_median_filter_2d(input, size=None):
-        return median_filter(input, size=size)
+        return median_filter(input, size=size, mode="nearest")
     def fast_median_filter_1d(input, size=None):
-        return median_filter(input, size=size)
+        return median_filter(input, size=size, mode="nearest")
diff --git a/python/lvmdrp/core/image.py b/python/lvmdrp/core/image.py
index 8e5c3eac..540610cc 100644
--- a/python/lvmdrp/core/image.py
+++ b/python/lvmdrp/core/image.py
@@ -1791,7 +1791,7 @@ def medianImg(self, size, propagate_error=False):
 
         new_data = fast_median_filter_2d(new_data, size)
         if propagate_error and new_error is not None:
-            new_error = numpy.sqrt(fast_median_filter_2d(new_error ** 2, size, mode="nearest"))
+            new_error = numpy.sqrt(fast_median_filter_2d(new_error ** 2, size))
 
         image = Image(data=new_data, error=new_error, mask=self._mask, header=self._header,
                       origin=self._origin, individual_frames=self._individual_frames, slitmap=self._slitmap)