Spur of the moment 5D mk III raw ISO test. Not a particularly scientific approach. I just wanted to see how the iso held up against the waining light from dusk till night.
I started out around Iso 2000 and ended up with around iso 6-8000.
As you see, the bayer noise that we start to see in the high iso end is not very pleasing to look at.
I'd say that make 3200-5000 is doable with a little love, but going past that is not going to look great. Imo, the 5D is pretty clean all the way up to 3200.
Gear and settings:
Canon 5D mk III
Canon EF 24-70 2.8L II
Canon EF 70-200 2.8L II IS USM
64gb Komputerbay 1000x CF card.
Aperture 3.5 in all shots. 180 degree shutter.
Turned off peaking, but had waveform and crop marks enabled and I was getting a good steady continuos recording with idle time as well.