What exactly is dynamic range? Shooting RAW vs. regular video

[Chris Davis]

Dynamic Range of the Canon 5D Mk. II

Dynamic Range of the Canon 5D Mk. II

...There is an absolute minimum value to what the Red sensor can capture, and an absolute maximum value. All values in between are captured, and the range of these values is wide enough that, assuming sensible exposure, the lowest value will usually be lower than the lowest value in your scene, and with proper care taken, the highest value will be higher than the highest value in the scene... What you can do is balance the tradeoffs of excessive noise (a problem as the absolute values get lower) and white clipping (which results when you hit or exceed the absolute maximum value) by playing with ISO settings and moving the captured values up and down the histogram as desired...

The dynamic range of the RED camera's RAW recording is good, but I wouldn't say that it's miles ahead of other digital cameras, or radically different than other digital cameras, and it's certainly nowhere near what color negative film captures. You may find that it has a stop or two more range than a typical video camera though...

So it's always a battle between noise vs. avoiding clipping highlights, which is digital's Achilles Heel. It cuts off overexposed detail suddenly and dramatically at the clip point. Lower ASA ratings, less noise, worse clipping -- higher ASA ratings, worse noise, less clipping. Which is why 320 ASA is more or less a sweet spot between the two ends...

I went back over some of these posts and I have a couple followup questions:

When I read this (above), I wonder if cameras that can shoot with higher ISO without grain would generally also have a higher dynamic range, because you can shoot at higher ISO and avoid clipping highlights, without adding noise to the darker areas.

For example, the Canon 5D Mk. II shoots ISO 1600 with almost no grain, whereas the RED ONE shows considerable grain at ISO 1600. Would you say that the 5D Mk. II has a greater dynamic range? Also if the ISO of the 5D Mk.II just metadata like Redcode RAW, and not burned into the RAW data like on DSLRs, would it be likely that the 5D Mk. II would have greater latitude than the RED ONE as well?

BTW, I'm meaning to compare the photos of the 5D Mk. II (not its video) with RED ONE video, just to better understand dynamic range/latitude. I also don't mean to imply that the 5D Mk. II's sensor is "better," as I realize it has enough rolling shutter artifacting to make it generally unsuitable for use in a video/digital film camera.

Thanks,
Chris

 

[Graeme Nattress]

5D2 burns in ISO, and actually does some burned in digital ISO too - worst of both worlds.

Graeme

 

[jake blackstone]

For example, the Canon 5D Mk. II shoots ISO 1600 with almost no grain, whereas the RED ONE shows considerable grain at ISO 1600. Would you say that the 5D Mk. II has a greater dynamic range? Also if the ISO of the 5D Mk.II just metadata like Redcode RAW, and not burned into the RAW data like on DSLRs, would it be likely that the 5D Mk. II would have greater latitude than the RED ONE as well?

BTW, I'm meaning to compare the photos of the 5D Mk. II (not its video) with RED ONE video, just to better understand dynamic range/latitude. I also don't mean to imply that the 5D Mk. II's sensor is "better," as I realize it has enough rolling shutter artifacting to make it generally unsuitable for use in a video/digital film camera.

Thanks,
Chris

You keep using latitude and dynamic range as interchangeable terms, which in fact are two different animals. Latitude is much more complex than DR, as it has to take into an account what is an acceptable image, vs. what is the difference between brightest and darkest parts of the image. 5D records video, while using H264 compression. Red uses a much more elegant compression solution. To give you an idea of the difficulty in quantifying the latitude, just try use some miss-exposed RAW image in Photoshop, convert it to JPEG and do some color correction to both. Which one do you think will fair better? What if RAW image is larger, but noisier? Which result will be better and at what size? All those aspects are difficult to quantify and are based strictly on empirical point of view.

 

[Chris Davis]

You keep using latitude and dynamic range as interchangeable terms, which in fact are two different animals. Latitude is much more complex than DR, as it has to take into an account what is an acceptable image, vs. what is the difference between brightest and darkest parts of the image...

Thanks. Any more explanation of latitude and dynamic range is appreciated. Also, I probably should have put this at the beginning of the post rather than the end, as I'm just wanting to compare sensors so I can better understand dynamic range and latitude.

..BTW, I'm meaning to compare the photos of the 5D Mk. II (not its video) with RED ONE video, just to better understand dynamic range/latitude...