The following is not a comprehensive technical reference for using the Zone System. It is intended to be more of a brief introduction and overview for those photographers interested in its use and application. I hope that this gives you an understanding that will further your learning when approaching the many great books on the technical aspects of the subject, some of which were used as reference for this essay.

The Zone system was developed as a means for the control of the tonal values on black and white negative film. It can be applied to other types and processes with varying amounts of success, though this essay will concentrate on the former. To make the most of the Zone System, it is all but necessary that you have your own darkroom in order to process your own film and prints. Not only will this make for more consistent results, but I also believe that completing the process in its entirety will make you an immeasurably better photographer.

What is a Zone?
When a meter (either handheld or in camera) is used to read a solid tone subject (a wall for example), the exposure information it returns will give a result of “middle gray.” This middle gray is 18% reflectance, the same tone as a gray card. In the Zone system, middle gray is called Zone V (5). This is the starting point for the rest of the zone scale.

Each Zone is one stop away from the next, that is half as much or twice as much light reaches the film. The lower Zones are darker on the print (thinner on the negative) the higher zones are brighter on the print (denser on the negative).

Zone 0 – the darkest possible black on the print
Zone I – the first tone above complete black
Zone II – the first signs of texture, slight detail
Zone III – dark areas with significant texture
Zone IV – dark foliage, etc in open shadow
Zone V – middle gray
Zone VI – Caucasian skin in sunlight
Zone VII – full textured highlights
Zone VIII – slight texture highlights
Zone IX – first tone darker than pure white on the print
Zone X – the brightest possible white on the print

Zones I – IX are considered the dynamic range (tones that will separate and have distinct tonalities between complete black and white)
Zones II – VIII are considered the textured range (tones that will show some or complete texture of the object)

How to use it:
The standard procedure for using the zone system follows the often heard and often confusing “Expose for the shadows and develop for the highlights.” When I was first trying to learn the mechanics of the Zone System a photographer I knew repeated this like a mantra and I never really could understand what he was talking about. I think that it is a phrase that cannot really be made sense of until the entire process is understood. I hope to avoid such confusion here.

We will start with the first part: “Expose for the shadows.” When you have found your shot and the camera is set up, the next step is to consider the esthetic implications of the scene. How do you envision it? Start with the darker areas of the scene. Imagine it as a final print. What tone is the ground (or tree or rock or wheel) in your minds eye? I think that this is the most difficult part of the Zone system for new users, because no one else can quantify it for you. There is no formula for deciding how a scene should look. You are the photographer and it is your choice.

Most commonly, users of the Zone System will look for an important darker subject in the scene that they want to have a certain amount of texture. Some look for Zone II, some for Zone III, and some for Zone IV objects, or shift between Zones II-IV depending on the subject. I use Zone III for most situations. I look at the shot and find something that I want to be dark but have full texture. Meter this area. Your meter has just returned an exposure value that will render that particular subject as Zone V (middle gray). This is the only thing a meter knows how to do. But we don’t want that particular object to be middle gray, we want it to be dark with full texture, this is Zone III. Zone III is two stops darker than the Zone V reading that the meter gave us, so close down 2 stops. This exposure will now return a scene with this particular object as we envisioned.

The rest of the scene will fall along the scale in proportion to our exposure determined above. Meter other important areas of the scene to see where things are falling on the scale. Pay careful attention to the highlights. Where are the brighter values falling in relation to our exposure? Find an important highlight area that you want to be a certain tone or have a certain amount of texture. Meter this area. Again the meter is returning a value that will result in Zone V. But, say for example that, we want this area to be Zone VII, the brightest area with full texture. Count the number of stops from the Zone III reading to this reading. If it is 4 stops away, then this exposure (with normal development) will result in that area being Zone VII as we had envisioned.

When our highlight value does not land on the Zone we envisioned for it, then we will have to adjust the development of the negative to adjust for that. Hence “develop for the highlights.” We can adjust the highlight value by changing the development time. This has no practical effect on the Zones V and below (though it does have some effect). So what we exposed for as Zone III, will pretty much stay Zone III even if we change the development to move the highlight value. If our highlight value that we wanted to see as Zone VII, was only reading 3 stops away from our Zone III reading, then normal development (N) would result in the highlight coming out as Zone VI. This would result in a flatter (less contrast) than desired print. By extending the development time, the highlight values will get brighter (denser on the negative). In this case, we might extend the development time to move the object that was reading as Zone VI, up to Zone VII. The exact amount of time required to do this entails running some tests. Conversely we can bring a highlight value down by decreasing development time.

Well, that’s basically it. Meter for the important shadow areas and expose for them as you see fit, then meter the important highlight areas and alter development to place them as you had envisioned them. It is interesting to note that this system is easiest to apply in cameras without any automation. Much of the advanced features and meters in newer cameras will only get in your way when trying to control your image. Modern cameras want to do all the thinking for you. But after the initial learning stage, I think that you will see that automation destroys creativity.

It is highly recommend that you run the Zone I (Personal Film Speed) and Zone VIII (Personal Development Time) tests outlined here, prior to implementing the Zone System for your work. Fred Picker’s book “The Zone VI Workshop” is a great reference source for these tests.

Meter types: A brief note on meter types. It is all but universal to use a spot meter for the Zone System. And I believe that the Pentax Digital Spotmeter is best suited to the task. It has a manual calculator which facilitates the placement of zones along the scale. It was not until I had one myself that the Zone System became second nature. Many of today’s modern cameras have a sophisticated matrix meter that consists of a complicated grid which interprets the scene. Meters such as these are very difficult to use for the Zone System, and require the user to fill the entire viewfinder with the object being metered.

Reference Books:

“The Negative” – Ansel Adams. The primary pioneer of the Zone System. This text is a bit technical and difficult to understand at times, though certainly thorough. Also, some of the information is a bit dated.

“The Practical Zone System” – Johnson. A good book to gain sufficient understanding of the Zone System. The information is much more current, though not as technical.

“Basic Photographic Materials and Processes” – Strobel. This book has a wealth of great information on all the technical aspects of photography. Of particular interest here, is the explanation of film curves and densities. I highly recommend this book, it is anything but basic.