>By dialing in additional base iso, all you're really doing is >delaying the point at which auto iso will kick in and start to >adjust itself upward, since you've already surrendered that >amount of lower iso from the get go. I don't see where >anything constructive has been accomplished. You might as >well keep the camera at base iso and only surrender the lower >iso values if and when necessary as determined by the auto iso >function .
I'm sorry, you are exactly correct. Mea culpa, I was thinking of this completely backwards.