If I were to rewrite the equation, I would... well... I wouldn't rewrite it. E=I*T is not a calculation of exposure. It is an expression of equivalent exposure, i.e.
reciprocity. As such, white balance is irrelevant. If I absolutely had to include ISO, it would be E=I*T*ISO. Increase any of the terms and one or two of the others needs to be decreased to keep the exposure constant. However, this changes the whole meaning of the equation, as changing the ISO implies changing the nature of your recording medium. E=I*T is meant to express the reciprocity characteristic of a given recording medium along the straight portion of the medium's characteristic curve. Outside the strait portion of the curve, the medium experiences
reciprocity failure. I realize that I have made this about as clear as mud. I have been up for too many hours. Take a look at this:
http://en.wikipedia.org/wiki/Reciprocity_(photography)
and then hit the really technical description here:
http://micro.magnet.fsu.edu/primer/p...mexposure.html