How much dynamic range do you need?

C

combatentropy

Veteran
Much discussion has been about exactly how much resolution you need for 90% of your work. While there is still some dissension and those who can never have enough K, it's safe to say that the limits of human vision falls somewhere around 2 to 4K, at least at traditional theatrical angles of view (30 to 40 degrees).

I have not heard much in regards to dynamic range. While more is obviously better, there is clearly an upper limit, after which come diminishing returns. For example, if the average daytime exterior held no more than 16 stops of dynamic range, there would be little use in having a camera that could handle 17, would there? I've also heard that after a certain point, things look fake. For example, in HDR photography, you can compose shots that span 20 or so F-stops, but the look is other-wordly.

Again, I'm asking you to put your 80-20 hat on, and not think in terms of marginal situations. If you were to do that, your appetite might be infinite. But for 80% of your work, how many f-stops do you need to render scenes as you want?

Real-life references are welcome additional material.
 
Last edited:
The camera I'm shooting with right now, the GH1, has around 9-10 stops I think, and it works well for me. I do wish at times (like a recent night exterior) that I could have another stop of two, but I added a little more light on the scene, and it came out great. I don't think I usually light for a greater range than 10 stops.

Now, when it comes to certain VFX work, more range can make the compositing a little easier.
 
hey combat, don't confuse tone mapping (the ugly fake looking images that you referred to) with high dynamic range

The human eye can see 18-20 stops
Film can capture 14 stops in its exposure range

I want my camera to capture as much exposure range as possible (9-10 stops is my minimum preference) and the rest I'll use light modifiers.

The gh1 and 2 (from what I've been told on dvxuser) is around 8 maybe 8.5 stops and this to me feels close. I have yet to see a chart on the gh2.
 
Last edited:
The max DR you will see out of any current display system is about 8 stops with dynamic contrast gimmicks, usually more like 6+ , the range covered by the standard 100 IRE video signal.
But if you want to capture images with film like gamma qualities, good shadow detail and pleasant highlight roll off you need at least 12 stops of usable DR. HDR is about gamma compression to represent the larger captured DR range in a smaller display range in a way that looks more like what the eye can see.
 
Last edited:
To make a beautiful picture...... anywhere between 7-15 stops is about all you really need.

The F3's sLog 13.5 is very comfortable, but i do occasionally, when shooting things like car interiors wish i had the extra "Alexa" stop. That said, the F3's DR is about perfect. Looks good, easy to build contrast, and captures just about anything.

My RED realistically captures about 12-12.5. Also totally useable. But remeber, HDRX is also an option. 18 stops if you like, i think it looks terrible, but its there.....


the rough evolution in DR indie digital:

1: DVX100 Limited to SD DV compression, 8 bit 4:1:1. had about 8.5 stops D/R. We all learned to light on this camera!


2: 1/3" HD: HVX200, HPX170, XLH1, XHA1 etc...
These cameras settled in the 9stop range. Still we continued lighting to the medium and nice looking things happened..... It was around this time that 35mm Adapters took over and that helped somewhat, they acted like HD Ultra con filters. turned the 9 into something more like a 10 stop Range. Helped sell the film look a lot. Still, we all worked within the limitations....


3:The 11 stop Barrier....
The 5D/7D/AF100 being the tipping point, still great latitude, but really missing the bottom stop because of noise/Compression. The additional 1-2 stops over the 1/3" cameras is a godsend. This is when things start looking more natural, and the "video" look started to die.

5D

AF100

4: The 12 Stop barrier. This is where interesting things start to happen. The image really leaves the Video look behind, and you get to place skin tones in the scene in a natural part of the tonal range. This is the territory of the The RED MX, Epic, Scarlet, C300 and F3(Non Log).

F3 (non log)
RED Scarlet


5: the +13 stop realm...
This is where the video image meets the latitude of film. The performance is stunning, and you can light with as much contrast as you like. The camera starts to respond more like your eye, and lighting choices can be bolder. This is the world of the Arri Alexa (14.5 stops), Sony F3 (13.5 stops), Sony F65 (14.5+), and to some extent the RED Epic/Scarlet with HDRX (12-18 stops), though its really not fully useable in all situation.

F3 w/ SLOG

Arri Alexa
( i had nothing to do with this one, all my Alexa projects are in Post right now, i dont have an example i own)
 
Ideal would be the 14 stops of film (or even more). Digital is already there and maybe even surpassing film as far as the shadows go. It's going from a little overexposed to blown out in a heartbeat with no roll off in the highlights that I usually fight against.
 
combatentropy said:
Much discussion has been about exactly how much resolution you need for 90% of your work. While there is still some dissension and those who can never have enough K, it's safe to say that the limits of human vision falls somewhere around 2 to 4K, at least at traditional theatrical angles of view (30 to 40 degrees).

I have not heard much in regards to dynamic range. While more is obviously better, there is clearly an upper limit, after which come diminishing returns. For example, if the average daytime exterior held no more than 16 stops of dynamic range, there would be little use in having a camera that could handle 17, would there? I've also heard that after a certain point, things look fake. For example, in HDR photography, you can compose shots that span 20 or so F-stops, but the look is other-wordly.

Again, I'm asking you to put your 80-20 hat on, and not think in terms of marginal situations. If you were to do that, your appetite might be infinite. But for 80% of your work, how many f-stops do you need to render scenes as you want?

Real-life references are welcome additional material.
Click to expand...


For film there are three parameters to consider. 1) Scene range that can be measured with a meter. 2) The acquisition range, in film film, the negative, which can be measured with a densitometer. 3) The presentation range, which for film film can also be measured with a densitometer.

Traditional 'print' output of film film based imaging, at least since the 50/60's, has been about 7 stops worth of range. I think movie print film has a similar range.

The point being... while a 'negative' may have a 12-15 stop range of capture... the output, the thing one sees projected, has a narrower range, and so, one must compensate.

With film film, one would 'cut' development if the scene range was beyond what the ultimate print range was, some combination.

What film film allowed though was the ability to 'over expose' or 'under expose', and use 'post' processing, in the form of development processing, etc. to compensate.

It seems that most DSLR's have about 6-8 stops worth of 'capture' capability, and so, this is the reason why it is so critical to get the 'scene' lit in such a way, as to maintain the image data values with in that range.

There is no equivalent to 'cut' development for the digital camera. There is a 'increase development' in the form of post processing the brightness and contrast of the image, but that usually also includes enhancing the 'noise'...

Film film also had this property, but some people liked the 'grain' of push processed film... but film grain is Noise...

As for your question, I think 10-12 bits of intensity quantization for a 'consumer/prosumer' camera, and codecs that maintain that... would be a good thing...
 
Thank you, all. And thank you, Timur, for the history. Very helpful.

Yes, I'm talking about captured dynamic range, as opposed to displayed dynamic range, which depends on my TV, and frankly, I would like to keep my TV set at 6 or 7 stops, because it's comfortable. A 14-stop TV would be kind of harsh on your eyes, I imagine. 12 to 14 stops captured, mapped down to 6 or 7, thank you. That's what Ansel Adams's Zone System was all about, by the way. Photographic paper also has a dynamic range of about six stops, and it was a way to calculate how to merge a scene of 12 or so stops down to it.
 
Last edited:
You must log in or register to reply here.
Back
Top