Bob, didn't you get tired of the different readings between the incident and the spot readings of your Sekonic 508? Also, I hated the constant underexposure the spot readings were giving. I changed for the Sekonic 608 where I can independently correct the spot (or the incident) readings, see the values in the viewfinder and be happy again... In fact, I suppose that Sekonic put there the independent corrections because they heard the criticism of fellow photographers over the spot underexposure and were tired to explain that it is "normal" for this product.