Quote Originally Posted by cliveh View Post
Isn't a light meter really a guessometer?
No! A light meter is a measurement instrument like any instrument. They have tolerances but no guessometer as you know the light level within the tolerances. Now an exposure meter is a guessometer. Because knowing the light level measuring as an average of the scene, a small spot or the intensity of light falling on the subject isn't sufficient to determine exposure. The photographer has to make a decision there.