High sensitivity has no advantages for bright light shooting. It just forces you to use very strong NDs and narrow apertures, or else the highlights look rubbish when pulled down to ISO 400 and under.
Leica discussed this with me at Photokina when I talked about a possible ISO 25 setting or a digital ND.
Look at the 'digital pull' image to ISO 25 for an example of the image quality problems when doing a very large pull from a high sensitivity & over exposed image.
Think of it in terms of dynamic range. At ISO 800, in bright light you're gonna get a lot of over exposure unless you shoot at a very narrow aperture, etc. etc. You can pull that raw data down to ISO 100. The camera does it with the image processor which is why it can offer the low ISOs. But to pull a native ISO of 3200 down to 100 is harder. Think of an over exposed raw still shot in daylight at ISO 3200. You can only pull it down so far in post. At ISO 3200 the exposure is going to be even brighter all else being equal - that requires even more latitude to keep hold of highlights. The roll off to highlights will become very steep when you pull the exposure down on that ISO 3200 raw, and some areas will be completely burnt.
I understand that, but how come in photography we have iso 100 - 6400 (or something like that) as native iso values, and in video there is only one native iso setting which is somewhere halfway the iso range? In photography the 1D C (or 1D X or any other high iso camera) doesn't suffer from bad quality on lower iso values. It's the opposite: the lowest values are always the best. Even on low light kings like the Nikon D3s etc. How come it doesn't work like that for video?
By the way, this new sensor has a pixel pitch of 19 microns. If it is fullframe, i'd say the sensor is 36mm wide. That would be 36000 microns. Divide 36000 by 19, and this sensor will have about 1895 pixels? I suppose they could stretch it a bit and fit 1920 pixels inside of it. But the max. resolution will be 1080p it seems.
I double checked this math with the numbers from the C300, 3840 pixels x 6,4 (pixel pitch) = 24576 microns = 24,576mm.