diff --git a/nd2reader/main.py b/nd2reader/main.py
index 7c2c0bb..e50d1f0 100644
--- a/nd2reader/main.py
+++ b/nd2reader/main.py
@@ -173,7 +173,7 @@ class Nd2(object):
     @property
     def pixel_microns(self):
         """
-        The width of a pixel in microns.
+        The width of a pixel in microns. Note that the user can override this in NIS Elements so it may not reflect reality.
 
         :rtype:     float