Originally posted by robgo2 Another drawback may be a shutter speed that is too slow for hand held shooting.
Well no, what I was getting at is that you shoot AS-IF the ISO was at 3200 or 6400 but keep it at 1600 and just adjust the EV. So you get dark images because you are still using the fast shutter, but then you pump them up later. In other words, beyond ISO 1600, that's all the camera is doing -- using software trickery to pump up the exposure. But you can do it yourself with possibly better tools later...