I've just photographed Duwayne Brooks, best friend of Stephen Lawrence. (He was with Stephen when he was killed). He was giving a guest lecture to some criminology students.
Now, the room he was presenting in was VERY dark, a little bit of light spilled in at the back around the drawn blinds, and there was a projector shining forwards, which provided a bit of reflected light. I'll be honest, my heart sank when I walked in, I didn't think I'd got a chance of getting anything useable. The first picture was taken hand held, 6400 ASA, 1/100th second at 2.8 on my 70-200 VR2. The second, was taken at 1600 ASA 1/125th second at 1.6 on my 85 1.2 G. Both pictures were shot on manual and have had a bit of post production work, but as I've said before, this is what the client sees, and ultimately, what can be produced. Now, I don't know about you, but I think the camera has performed brilliantly here, the WB is spot on, and the noise is very well controlled. Remember I'm coming at this from the perspective of a D3s owner, but I can tell you, I wouldn't have got anything this clean on the D3s. I hated taking the D3s above 4000 ASA, and now I'm dialling in 6400 without thinking. The D4s, in real world situations, seems at least a stop and a half cleaner than the D3s, perhaps even two stops.