Old Setup
5DII - 14LII/16-35mm on tripod as static cam
5DII/7D- 35L/50L on Redrock Rig
5DII - 85L/135L on fluid head
This was my general setup for recording bands over the past year. Camera 3 ALWAYS looked significantly better than the others, as the 85/135 are amazingly sharp lenses and very detailed. When I only had the 16-35mm the static cam always looked like it was lacking a bit compared to the others, but the 14mm helped make it look much more consistent. Either way, cam 3 always stood out in terms of IQ.
New Setup
5DIII - Zeiss 21 f/2.8 (Shot at f/2.8 entire time, ISO between 1250-1600)
5DIII - Zeiss 50 f/1.4 (Shot between f/2.0-f/2.8, ISO 640)
5DII - Zeiss 85 f/1.4 (Shot between f/2.0-f/2.5, ISO 320-640)
First off, I have to say that I dont know that I can ever go back to shooting video on Canon lenses after using Zeiss glass, more on that later. As for the 5DIII, I have to say it was an absolute joy to shoot with. I don't care if the 1080p signal has overlays, I can't tell you how much easier it is to pull focus with these cameras. I normally use the Zacuto EVF on the rig and for once I could just use my 5" Marshall and it was just fine (but never with the 5DII).
Got home last night and started checking out the footage and was very, very pleased.. People complain about lack of detail with the 5DII/III, but it looks plenty sharp with no post-sharpening and it handles noise much much better than the 5DII. I think it's sharp enough that only a pixel-peeping gear-head would ever complain about the IQ of this thing. Sure the resolution could be better, but that doesn't mean it's unacceptable. The only time I could call footage from these cameras "muddy" is when shooting with absolutely no extra light in a low-light situation, but hey what do you expect? Shooting with proper lighting makes all the difference in the world.
Here is the kicker, the static cam with the 5D3/21mm 2.8 @ ISO 1600 looked better than the 5D2/85 @ ISO 640 (which was always the money shot before)! This is the first time ever that the tight shot wasn't the absolute best, it was actually the least impressive of the 3. I think that says a lot about the 5DIII. It took a real shoot for me to truly see the difference..and I didn't have to look hard to see it. I was also very surprised by how well the internal mic picked up bands making that much noise. We are using $50k worth of audio equipment, so it wouldn't work for my situation, but I can see it being usable in some cases.
As for the Zeiss lenses, the things are just amazing. They are very sharp edge to edge and do very well with fine detail, the focus rings are smooth as butter, they breathe much less than the Canon lenses. They are built like tanks and the sound and feel of the lens hood locking into place feels awesome for some reason. The throw of the focus rings is just superb, and having hard stops at infinity and macro makes all the difference in the world. Color rendition is absolutely amazing and the footage looks superb straight out of the camera. Minimal color correction required, I spent probably 1/4 of the time I normally do with Canon lenses. Anyways, after shooting with these guys there is absolutely no way I could recommend a video shooter buy any L lenses (unless they need something longer than 100mm or shoot lots of stills and need AF). I really wish I had just bought them in the first place, as I am pretty attached to my L glass and am having trouble bringing myself to get rid of them.
In short, 2 thumbs up for the 5DIII and same for Zeiss glass.
Edit: I will post the videos as soon as I get clean audio from the engineer and the videos get approved for release.