Quote Originally Posted by peety3
just doesn't fly. Nowhere in either of those bulleted points is there a measure of light per area. There is merely a length of time, a diameter value, and an approximate sensitivity of an imaging sensor.

I think we still have a misunderstanding. I think the confusion started when my statement made it seem like exposure means the same as "f-number and shutter". I should have made it more clear that they are not the same (nor did I mean to imply they were the same.)


I think this is how you interpreted my statement:
  • The camera settings (f-number, shutter speed) are the same, therefore the total light (exposure) is the same.



That would be wrong, because as you mentioned, it fails to account for the many other factors that can affect total light.Here is what I was trying to say:
  • Exposure is the same, therefore the total light is the same. Also, The camera settings happen to be X, Y, and Z.



I could have put it this way:
  • Both shots have the same exposure, because they have the same f-number, same shutter speed, same lens transmissivity, same 0.3 ND filter, same linear polarizing filter, same 50 GN flash, same 300 lux/s scene luminance, same aperture activation variance, and same shutter activation variance.



But it's a lot simpler to just say they have the same exposure, because it means all those other factors are the same as well.


Sorry for the confusion.