Quote Originally Posted by RalphLambrecht View Post
the analog analogy equivalent of the exposure triangle is the exposure waterbucket.the aperture is the size of the valve;time is the filling time and ISOis the size of the bucket. the object is to fill the bucketto the rim. too much waterand the bucket overflows=over exposure;not enough water and the bucket is not full=under exposure;filled to the rim is perfect=perfect exposure;so whatever you change (aperture,shutter speed orISO)just make sure to fill the bucket;anything goes,but with analog,the bucket has a fixed size.
Exactly but by the meaning of the word exposure only the amount of water is the exposure. The size of the bucket doesn't matter. It does make the water run over or too low in the bucket BUT that's the results of a specific exposure (a specific amount of water) on a different film emulsions (different buckets) have the different results yes but the exposure (the amount of water allowed to the bucket) is the same given the same subject brightness (water supply pressure), aperture (size of valve opening) and exposure time (filling time) you get the same exposure (same amount of water going to the bucket). My argument is that the term exposure in and by itself does not involve sensitivity.

The exposure which is measured in Lux.Sec is only intensity x duration. The sensitity isn't the exposure.