Alls I know is that that my FE has never given me the wrong exposure. It simply boggles my mind. I even shot it with Velvia at 40 and no problem. There's a very difficult, cave like building that we set it up on a tripod, I light metered for my large format camera and came to about 2.5 minutes, set the FE on there, and it exposed for 3 minutes. Compared side by side, the FE was better than I.