David Mullen ASC
Moderator
I'd also add that since underexposure mistakes tend to look worse than overexposure mistakes, by rating the stock only 1/3 of a stop slower, which is very conservative, you may not really be overexposing much, it might just be a protection against slightly underexposing because 1/3 of a stop is within a margin of human error in exposing shot by shot.
