I recently rechecked some of my lenses' DOF scales against an online calculator and found one particularly anomalous. Let me say that I am aware of the various CoC issues respecting DOF determination and magnification in printing, and recognize that manufacturer often create lens scales based on a relatively small enlargement, meaning that a good stop down additionally is likely to be advisable. However, my lenses have aligned pretty well with an online calculator I use. The one that is rather glaringly off is my 55mm f/2.8 Mamiya-Sekor for my 645, and I wonder if anyone else has noticed this. I have three other lenses for the camera that are generally pretty close, as are my Leica M's, so I don't know why this one would not also be.