Cleanest Footage Possible

coddida said:
Bold emphasis added by me.

Hurlbut says that native ISOs are 200, 400, etc. Tim Smith says they are 160, 320, etc. I consider that a debate. They can't both be right.
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I don't think there's a "debate" as much as a mixing of nomenclature. Up to a week ago, I never even heard the term "native ISO." And I spent hours and hours researching the 5D MKII before buying one. I think some are calling the true ISO's "native" and some are calling them "true."

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And, I'll add, Shane so far is the only person I've heard claiming extended dynamic range in between the "true ISO's" which may very well be true, and would make some sense since I'd imagine it could mean some form of processing is at play at those ISO's not unlike the Cine Gamma settings on an HVX200 which yes, allow for more range but give more noise at the same time.
 
Let's end this once and for all:

5D's native (aka 'true' ISO) ISO numbers: 100, 200, 400, 800, 1600, 3200, 6400

5D's ISO numbers with lowest noise (aka 'faked' ISO) for video: 160, 320, 640, 1250, 2500

Trade-off: The 'faked' ISO numbers give lower noise because of a hardware noise reduction process that occurs. The trade-off is that 1/3 of stop of dynamic range is lost at the top end (the highlights). The 5D can (on average) capture about 7-8 stops, so clipping 1/3 of a stop off is hardly going to be noticeable. But... there you go: Faked ISOs give cleaner image with 1/3 of a stop less dynamic range.
 
I also wanted to add to this, which is a little outside of the camera functionality.

I've been using the 5D Mark II for some time and having it projected in theaters. I really don't recommend shooting past ISO 1250/1600.

If you have to get the shot though, I've actually had pretty good results using Neat Video on ISO 2500 and 5000 clips and that can really save the day.

Also, in terms of exposure, I tend to underexpose slightly than what is considered a normal exposure. There are certain tricks you can do to pull back some highlight detail in the clipping range, but if you get too much of it, nothing will look good. So I recommend protecting those highlights the best you can.

That said, this camera handles overexposure/color saturation pretty well considering all things.
 
Nail on the head. Thanks tfg!

Our testing showed if you turn on highlight tone priority for the faked iso's you get that highlight info back. Turn it off for the native iso's.
 
I'll get flamed but here goes.

There is only ONE native iso (Strictly an EI, since iso is a film speed) and that is the lowest unprocesed "iso", in the case of Canon cams 100. Check out the published dynamic range / noise / resolution, they're highest at iso 100, and go down either side.

Higher iso values are by amplifying the signal, and the intermediate vlues are by under or over exposing the 100 200, 400 etc. The shadow noise decreases at the expense of highlight range, as tfg has said.
Dave
 
daveswan said:
I'll get flamed but here goes.

There is only ONE native iso (Strictly an EI, since iso is a film speed) and thati s the lowest unprocesed "iso", in the case of Canon cams 100. Check out the published dynamic range / noise / resolution, they're highest at iso 100, and go down either side.

Higher iso values are by amplifying the signal, and the "low noise" are by under or over exposing exposing the 100 200, 400 etc. The shadow noise decreases at the expense of highlight range, as tfg has said.
Dave
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nah Dave -- we're still talking the same language. The sensor base is 100 ISO - correct. The difference is that the sensor can (on its own) do 200, 400, etc. It needs secondary help from other noise/light processing elements to create those 'fake' ISOs. Regardless, all the stuffs we talked about at the various ISO settings apply the same.

Hence why I referred to them as "true" ISOs rather than just 'native.' Semantics, but meh, whatever :)
 
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One basic thing to consider with the 5D2 as well is that it's better to shoot a bit higher ISO and have the proper exposure than to shoot at a lower ISO and then compensate in post. People often think that higher ISOs are a bad idea. You actually end up with a cleaner ISO 400 image that is properly exposed than shooting at ISO 100 and having it underexposed. ISO 100 can be really noisy actually if you have to compensate upwards in post. Especially in the shadow areas.
 
Chris Santucci said:
I'd rather take the advice of pros using the 5D who are getting great results because it saves me time having to do tests on my own and I'm OK with great results.
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Definitely! I would never have the gall to question guys like Shane and Gale. I wouldn't question Jeff Gordon either if he told me to use a particular type of oil. These guys know their stuff, end of debate. (even though I haven't heard of any debates...I thought this stuff was common knowledge.)

I haven't heard of aiming for higher exposure than what the light meter is telling you...I'll have to try that out! :)
 
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