Having just got my hands on a Canon 6D and thought I'd test out the ISO.
The idea is to see how well the camera performs in a low light situation.
This test is nothing scientific, only going through the native ISO range and seeing how the camera reacts panning from dark to light. I must say I'm impressed.
You can download the clip to see the original for full scrutiny.
Alternatively... here's a zip containing screenshots from the original clips: dropbox.com/s/k9xj6j093p29gix/Canon%206d%20ISO%20Screenshots.zip
I'm using a 50mm 1.4 lens at a shutter speed of 1/50 s.
Also... using the CineStyle profile which you can grab from here:
I hope to post more tests as I get to know the camera, meanwhile drop a question in the comments if there's something you want to ask about the 6D.