2F/2F:
OK. That makes sense. I was incorrectly thinking that reducing the ISO # decreased the exposure by allowing less light and therefore required compensation. I was thinking that this was a negative adjustmen, i.e. 400 to 25 was a negative 4 stops when it sounds like it should be a plus 4 stops. This will make me rethink my overall adjustment logic. Thanks for setting me straight. I really appreciate the feedback.