I've been shooting my strobes manually, but am trying to use the E-TTL occasionally. I'm not sure how it all works. I use PocketWizards (the new smaller kind) to trigger the unit - I know the camera meters through the lens, but does the flash unit do a separate distance calculation, or does the camera assume the flash about equidistant from the subject? I'm not waiving it around wildly, my arm is only so long, but sometimes working close in the distances matter. Also, I can't seem to stop down the flash power on the unit while set to E-TTL. So do I do it on the camera? Or do I shoot in Tv and then dial in a little more aperture? 580 EX IIs on 1Ds Mk III or a 5D.