Quote Originally Posted by Daniel Browning


(By the way, they have the same "exposure" but different "brightness". The idea that ISO is a part of exposure is a common misconception.)

In a purely digital world, you may be right. In the days of film, f/4 and 1/500th might underexpose some film and overexpose other film. Otherwise, Bryan Peterson must be wrong in calling it the Exposure Triangle...and he's certainly sold a lot of books calling it that.