About the photograph “Morgan’s Song”, when you said that you burned her dress (in order that it is not lighter than …), how do you do Burn/Dodge in digital ?

Thanks!

You might even make your own thread about ETTR. There’s some debate about it in the industry and I think it bears discussion.

Gav

I’m not trying to claim that the zone system should or even could be replaced by ETTR. I think seeing and using zones is still a very valuable skill to possess, and a great way to determine your final exposure. It’s just that I mean the exposure you have after post-processing, not necessarily the one you get directly by taking the picture.

I, too, don’t consider extra information in the file for the sake of it important. As you said, in the end, it’s all about the main subject being exposed as good as possible to achieve the greatest image beauty and quality. But I believe that using ETTR while taking the picture and then post-processing according to my artistic vision utilizing the zone system to get the desired look, maintains the greatest possible image quality, which in turn provides more leeway for postwork and thus potentially more beauty.

In the end, it’s up to everyone to make up their mind how they expose and post-process. I just wanted to mention ETTR since it can be used instead of or, to even greater benefit, together with your zone approach.

Personally, I don’t use ETTR all the time, because often there’s not enough time, so matrix metering is used and exposure compensation dialed in based on guessing and experience. For most cases, that’s just fine, but if you have the time and the image is important enough to warrant the extra effort, I’d use it to keep more options to post-process and maintain the greatest image quality.

By the way, after posting my comment, I started to look around some more and found a recent article on another blog which, to say the least, gets one thinking very much. I’m sure we all instinctively know the answer to the question how to expose a black cat sitting on coals or a white cat on snow. But considering the difference between film and digital in this case is really mind-blowing.

I don’t want to further derail the topic “Zone System” with ETTR discussions, especially with my long comments, but I really want to share a final link with you. It should get you thinking again, as it did for me, and I hope you’ll find it as insightful as I did: http://www.luminous-landscape.com/tutorials/optimizing_exposure.shtml

Kind regards
– Stefan Daniel Schwarz

As for ETTR (Expose to the Right). It’s a good thing to understand, but it’s not really a system of exposure. The Zones are. I don’t find digital exposes all that differently (though it has less range of course) I’d say ETTR is a fair guideline for when you’re eon the run and wanting to capture all the range you can. Expose a bit light while making sure you don’t clip your highlights. But to me it pretty much ends there. The idea of overexposing for the sake of it is fundamentally flawed. It does not negate the Zones because if you understand and use Zones in exposure and processing you know “exactly” what you’re getting and you get exactly what you want. It’s trueI generally like to see an exposure that has no highlight clip and little or no black clip. Because of that I may vary for the absolute Zone value to give me the range I feel I need.

I consider extra information in a file for the sake of it of less value than nailing what you envision. The better the main subject is exposed, the better the image both in beauty and quality.

If you want to apply ETTR the Zone system does not become invalid. The “best exposure” is the one that makes your subject look as good as possible. I say expose dead on in most cases, but if you visualized and planned your scene, then gave another 1/2 stop for a bit extra in the shadows, you should be cool as long as you don’t clip the light. But even with that, the System if Zones is no less valid. Zones are a system for seeing and managing light and most people don’t use it because they don’t understand it or are not willing to discipline their light control on that level.

Thanks for getting me thinking. I like looking at all methods being used, though generally I find their principles can slide right in as weapons in the arsenal along the Zone system. Gav

nice introduction to the zone system with interesting information. Yes, it’s a great way to see and visualize light.

As you described it here, it allows the photographer to expose an image as (s)he wants to, so the picture taken looks like the image envisioned out of the box/camera. If that’s what you want, this is a viable approach.

However, there is a reason why the zone system isn’t referenced or taught as much with digital photography. There actually is an important difference between digital and analog photography which makes the zone system, as described and used here, less relevant today.

The reason lies in how digital imaging sensors process light and produce noise: If there’s a lot of light, the signal is stronger than the sensor’s own noise, and thus the information is recorded properly (good signal to noise ratio). When there’s less light, the signal is weaker and harder to distinguish from the sensor’s noise (bad signal to noise ratio).

You can easily see this when working with high ISO values. The noise is strongest in the darker areas whereas it’s much less of a problem in the lighter ones.

So, the brighter an exposure, the more information (and less noise) is recorded in your image. Of course, there’s also a limit there, and if the sensor’s dynamic range is exceeded, the brighter areas will burn out and result in a complete loss of information there.

Considering these technical limitations, the best exposure – the one where the most information and least noise is recorded – is the one where we get the brightest image without burned-out highlights (in relevant areas). Then this image can (and should – if it turned out brighter than desired by the photographer) be post-processed optimally.

You can easily achieve this kind of exposure by spot-metering the brightest, relevant part of your scene and dialing in positive exposure compensation until it’s at the brightest value which still doesn’t burn out. That value depends on your camera model so you have to find it out for yourself, but thanks to the blinking overexposure warning you’ll know when you’ve reached it or when you’ve gone too far.

When post-processing, you’d lower the exposure to achieve the look you envisioned. Then you can dodge and burn to your heart’s content, knowing that your capture included as much information as possible (with a single capture).

If you chose a different exposure, you’d have lost information: Any brighter exposure and your brightest areas would have burned out (since we already got them as close as possible to the limit), any darker exposure and you’d have sacrificed signal to noise. So this really is an objective optimum, not a subjective choice.

With this capture, you can get any other exposure you could envision through post-processing: You can lower exposure globally or by burning locally, and you can raise exposure globally or by dodging locally. You can selectively raise or lower highlights, midtones or shadows.

This exposure technique is called “Expose to the Right”, because the histogram will usually show that most information is in the right (brighter) half and less information in the left (darker) half.

If you’d like to combine exposing to the right with the zone system you described: Instead of placing your subject in any zone of your choosing, place the brightest part at zone IX. This gives you the optimum dynamic range and signal to noise ratio possible with a single exposure.

Well, that’s my humble attempt to explain this technique, and apparently quite a long comment. There’s much more and better information if you search for it online, even a Wikipedia article here: http://en.wikipedia.org/wiki/Exposing_to_the_right – recommended further reading!

Kind regards
– Stefan Daniel Schwarz