Most of us have experienced the feelings that accompany any big change; a combination of fear juxtaposed with excitement. First leaving home for college or starting a new job, or maybe picking up our first film camera, or making the jump to a new format. Sometimes we let fear get the better of us and delay our journey. Some of us quit before we even start. Change can be scary, yes, but it’s also the only way to grow and develop. When we finally work up the courage to embark on one of life’s new paths we realize there’s nothing to fear.
The climb to every summit inevitably starts with the first step, so the platitude says. This article serves as the first step in what will be a multi-part series surrounding mastering the technical aspects of photography. You will read a lot about Ansel Adams and the techniques he developed, how they forever changed our understanding of exposure and the precision with which it can be controlled. These techniques are universally relevant across all types of photography, from large format view cameras to the latest whiz-bang mirrorless marvels.
Before we begin, I think it’s important to get something out of the way – whenever a discussion of the technical comes up there is always an apparent conflict with creativity. Don’t get me wrong, there is absolutely a subset of photographers who love playing with densitometers and plotting curves. Conversely, there are also those who rely solely on creative or intuitive methods. Neither group is necessarily wrong, but both are likely coming up short of their desired results.
Technique is like a tool in your toolbox – it doesn’t always have to be used, but it’s there when you need it. Don’t be that person who says they are a natural light photographer simply because you don’t know how to use flash. Don’t say you don’t bother with exposure calculations because you don’t understand them. Instead, lets work on improving our skill and mastering our craft.
Technical mastery is freedom. When we can control our process and know what results we will get, we will be free to create whatever kind of photograph we want. We don’t have to bracket and hope for the best. We don’t have to wonder if our image will turn out. With the proper technique, we know.
Ansel Adams and the Development of the Zone System
Few people have the unique ability to be both a skilled practitioner and a good teacher. Ansel Adams was an exception. He not only became the most well-known photographer in his time (and since), but has left behind in writing all of his knowledge for those of us who care to learn it.
For Ansel, mastery wasn’t always the case. He admits in his book, The Negative, that his early days were spent working via trial-and-error. His decades of experience allowed him to utilize intuition, like developing for more or less time depending on how contrasty a scene was, but he admits, “The process on the whole was empirical, uncertain, and often fraught with failure.”
It was when he began attempting to teach others that he noticed his own shortcomings. The only thing he had to offer students was a demonstration of his own particular technique with the hope that they would be able to arrive at a similar result through their own experimentation. His analytical and scientific mind drove him to develop a new technique that would not only deliver precise, predictable results, but one that would apply to any genre of photography.
Ansel Adams developed his famous Zone System along with Fred Archer at the Art Center School in Los Angeles in the 1940s. The roots of their system were based on the experiments of John Davenport, who demonstrated that the same density on a negative could be achieved with different amounts of exposure by changing the amount of development. Consequently, the Zone System is rooted in sensitometry, which is the measurement of light transmission through a negative.
The genius of Adams and Archer’s technique and the reason all of this mattered and still matters is that they developed a metering and processing method that allows the user to measure the light and achieve the result they want whether it be a literal representation of the scene or a dramatic departure from it.
There are ten zones in the Zone System, and each zone represents a difference in exposure of one stop. The zones range from total black at Zone 0 to pure white at Zone X. Zone System Metering allows us to take a light meter reading of a subject and place it anywhere on the range of tones from total black to pure white. I should add that although the majority of this series discusses (and will discuss) black-and-white film, the principles are the same for color negative film, color slide film, and digital imaging, with certain considerations (which I will cover later in this article).
|Low Values||Zone 0||Total black in print. No useful density in the negative other than filmbase-plus-fog.|
|Zone I||Effective threshold. First step above complete black in print, with slight tonality, but no texture.|
|Zone II||First suggestion of texture. Deep tonalities, representing the darkest part of the image in which some slight detail is required.|
|Zone III||Average dark materials and low values showing adequate texture.|
|Middle Values||Zone IV||Average dark foliage, dark stone, or landscape shadow. Normal shadow value for Caucasian skin portraits in sunlight.|
|Zone V||Middle gray (18% reflectance). Clear north sky as rendered by panchromatic film, dark skin, gray stone, average weathered wood.|
|Zone VI||Average Caucasian skin value in sunlight, diffuse skylight or artificial light. Light stone, shadows on snow in sunlit landscapes.|
|High Values||Zone VII||Very light skin, light gray objects, average snow with acute side lighting|
|Zone VIII||Whites with texture and delicate values; textured snow; highlights on Caucasian skin|
|Zone IX||White without texture approaching pure white, thus comparable to Zone I in its slight tonality without true texture. Snow in flat sunlight.|
|Zone X||Pure white of the printing paper base; specular glare or light sources in the picture area.|
It will be useful to reference back to these zones frequently and commit them to memory or create your own chart to stash in a camera bag or wallet. Tattoo it on your arm if you’re really committed.
Tools of The Trade – Light Meters
You might have surmised it would be difficult to discuss the topic of Zone System Metering without talking about light meters. Before we get into specific models, it is important to understand the two basic forms of light measurement: incident and reflective.
Incident meters measure the light falling onto a subject. They are the meters with the white globe that portrait photographers shove under a subject’s chin. They are incredibly useful and accurate meters when your subject is in close proximity to you and in the same light. Because they measure the light falling onto a subject instead of light reflected off of it, the different tones or light values of the subject will register on their proper zone automatically. There are certain methods that are variations of the Zone System that use incident meters, but for the most part the Zone System relies on reflective metering.
Reflective meters measure the light that is reflecting off of a subject as opposed to the light falling onto it. Unlike incident meters, reflective meters require interpretation from the photographer. A dark subject reflects less light than a light subject because they possess different subject luminance. As a result, a measurement of the highlight and shadow of a subject in the same light will produce dramatically different meter readings. The biggest advantage of reflective meters is that the photographer does not need to be in the same light as the subject. It would obviously be impractical to hike to the top of a mountain to obtain an incident meter reading in a landscape. Although reflective meters may seem more difficult to use initially, they are the type of meter that opens up the world of creative interpretation via the Zone System.
With both types of meters, it is important to remember that they are machines and incapable of interpreting the light they are measuring. All meters are calibrated to 18% gray or Zone V. Therefore, unless you are metering a gray card or a subject that is equal in luminance to middle gray, your exposure will be off without adjusting your exposure up or down depending on where it falls among the different zones. In order to isolate the different tones of a scene and obtain the most accurate reading, we want our meter to measure the most narrow area possible.
With the different forms of light measurement out of the way, lets discuss some specific examples of meters and how they may or may not be suited to our needs.
In-Camera Meters – In-camera meters are reflective meters. They have varying utility to the Zone System depending upon the size of the area which they measure. Average meters measure the entire frame and are therefore relatively useless for isolating different tones in a scene. Center-weighted meters take in a large portion of the frame with the emphasis being on the central 20-30% and are therefore slightly more useful. Most modern cameras and some vintage cameras come equipped with spot meters, which are ideal for the zone system, although some have larger fields of view than others. Matrix meters are a more recent development and attempt to replicate the Zone System by taking multiple measurements within the frame and then using an algorithm to predict the type of scene being captured. The camera can then adjust the exposure accordingly. Although some matrix meters are extremely good at dealing with tricky lighting situations, they remove the creative input and wrestle control from the photographer.
Smartphone Meters – Metering apps on today’s smartphones are reflective meters. They utilize the phone’s camera to measure light. If your camera doesn’t have a built-in spot meter, this is the cheapest (i.e. free) way to start experimenting with the Zone System. The downsides are that the area in which the meter reads is typically pretty large and you have to hope your phone doesn’t die while shooting. An exception to the phone camera meters is the Lumu meter, which plugs into your phone and functions as an incident meter.
Incident Meters – Sekonic L-308, Sekonic L-358, Gossen Luna-Pro, etc. These meters are great for studio use and up-close subjects, but not for the Zone system.
Combination Incident/Spot Meters – Sekonic L-508, 558, 758, etc. This type of meter combines the best of both worlds with separate incident and spot meters. If you want a single meter that can do everything, I would recommend something similar to this.
Pentax Digital Spot Meter – This is my preferred meter for Zone System use and my recommendation for anyone who wants to get serious with this technique. It is only a spot meter and is extremely simple in operation. It measures a one-degree spot through a massive viewfinder. It reads reflective light in terms of exposure value (E.V.) and reads in one-third stop increments. The reason this type of meter is superior to other types of spot meters is because of the scale that rotates around the lens.
Although complicated in appearance it is extremely simple in use. It allows the light reading to be placed in any zone quickly and without counting stops in your head. The E.V. system allows you to see all equivalent exposures at the same time depending on which aperture or shutter speed you want to use. It is rugged and simple in design, and runs virtually forever on a single battery.
Practical Application of Metering Technique
Now that we understand the basis of the Zone System and how different light meters work, let’s dive into how to put this metering method into practice. You have most likely heard the phrase, “expose for the shadows and develop for the highlights.” We will get more into the develop portion in a later part of this series, but for now we will focus on the “expose for the shadows” part.
In black-and-white negative film, the shadows represent the areas of the negative with the least amount of density. These “thin” areas allow the most light to pass through the negative, which results in a darker positive print.
Looking back at the chart of different zones, we see that Zones III through VIII represent the “textural zones.” The important parts of our scene must land in this range in order to retain detail. We can control highlights to some degree through development techniques and printing or editing in a hybrid workflow, but there is no way to recover shadow details that are not recorded on the negative. Therefore, in most instances, we determine our overall exposure by placing the shadows where we want them and then evaluating where other parts of the scene fall along the different zones based on that exposure. A greater number of zones between highlight and shadow represent a scene with higher contrast.
Procedure for Zone System Metering
- Evaluate the scene and visualize how you want the final print to appear.
- Take a meter reading of the darkest part of the scene that needs to retain shadow detail and place it in Zone III. (Remember that all meters read for Zone V. In order to place a reading in Zone III, it needs to be two stops darker so either increase shutter speed by two stops or close down aperture by two stops). This is your exposure.
- Using the exposure you set in Step 2, evaluate other important areas of your scene. The brightest important highlights that need to retain detail should be no more than 3 stops over your exposure (i.e. Zone VIII)
As with most things, understanding comes from practical application. Below are some real-world examples of Zone System Metering.
This first series of images above, along with the second series below, illustrates how your meter tries to make whatever you are metering land in Zone V. In the first image, I metered the darkest shadows (the exposed roots on the hillside in the middle of the frame) at E.V. 12. I decided to use an aperture of f/11 so my shutter speed was 1/125th for TMAX 400 exposed at box speed. In the second image, I metered the highlights (sky) at E.V. 17, which gave me an exposure of f/22 at 1/1000th. There is a five stop difference between these exposures because the meter automatically places each reading in zone V. You can see in the two images that the tonality of the roots and the sky is the same. The third image was made by placing my initial shadow reading of E.V. 12 in Zone III, which gave an exposure of f/16 at 1/250th. At this exposure, the sky fell into Zone VIII, which is within the tonal range of the film.
In the example above the important shadow detail was the pole in the foreground metered at E.V. 12. The brightest important highlight was the white metal roof of the barn in the background, which I metered at E.V. 17. My exposure in the third image was made at E.V. 14, which placed the pole in Zone III and the roof in Zone VIII
In the image below we see a good example of how a meter can show us things our eyes cannot perceive. The gravel in the foreground appeared darker to my eye than the blue sky, but they both metered at E.V. 16 and you can see they are the same tone when reproduced on black-and-white film. The roof was E.V. 17 and the pallets were E.V. 15. My exposure was made at E.V. 16, which made both the gravel and sky Zone V, the roof Zone VI, and the pallets Zone IV.
The color image above is a simple cell phone photo of the scene. I metered the shadows (dark areas of trees and grass under tongue of trailer) at E.V. 10 and placed it in Zone III on my meter’s dial. The highlights (brightest reflection on Airstream) metered at E.V. 15 and fell on Zone IX. This was fine for this scene as the bright reflections did not need to retain textural detail, but are not totally blown out either.
In the image below, the most important detail to me was the clouds. I wanted them to pop with brightness, but not lose detail. The brightest section of clouds metered at E.V. 15 2/3, which I placed on Zone VIII. The fence fell just above Zone VI and the grass at Zone V. If I had placed the grass in Zone III, the brightest cloud would have fallen on Zone VI and the scene would have appeared muddy and dark.
The photo above was taken moments after the previous example and was metered similarly for the highlights. The brightest clouds registered at E.V. 15 and were placed on Zone VIII. The grass fell on Zone V with the darkest areas of shadows in the leaves of the tree creeping into Zone II. Raising the exposure of the leaves to Zone III would have resulted in a loss of detail in the clouds.
The image below is another example of placing your most important value where you want it and evaluating where other tones fall along the scale. The windmill is white and metered at E.V. 16, which I moved to Zone VIII. The clouds also fell on Zone VIII, the stones in the foundation of the windmill are Zone VI. The trees in the background are Zone IV with the shadows at Zone III.
Color Slide Film – The Zone System is not only applicable, but a virtual necessity for predictable results with slide film. Slide film has a more narrow exposure latitude than black-and-white film. Because slides are a positive instead of negative image, our most important detail is the highlights instead of the shadows. Similar to underexposure in black-and-white, over-exposure in slide film results in clear film base with zero detail. Therefore, it’s important to preserve highlights at all costs when shooting slides. Generally speaking, you have about two stops of useful dynamic range on either side of Zone V. When metering it’s important to make sure highlights don’t extend beyond Zone VII or they will be blown out. Shadows below Zone III will be black.
Color Negative Film – Color negative is basically Zone System on easy mode. Modern color negative film has tremendous exposure latitude on the side of over-exposure. However, like black-and-white film, under-exposure is bad news. Under-expose your image and shadows will appear muddy with increased grain and color shifts. When metering, place your darkest shadows no darker than Zone III and let your highlights go as high as they want; you won’t blow them out.
Digital – Think of digital as a combination of color negative and color slide film. By this I mean that modern digital sensors have amazing performance. They have huge dynamic range and produce clean images at ISO settings film could only dream of. They also avoid all the headaches of reciprocity failure when exposures extend beyond a few seconds. The only worry is over-exposure. Like slide film, if your highlights blow out on digital you can kiss them goodbye. When shooting check your histogram and as long as your highlights aren’t clipped you’re good to go.
What’s the point?
Above we see a flat scan on the left and a final darkroom print on the right. I placed the shadows underneath the waterfall on Zone III. The majority of the highlights (snow) fell on Zone VIII except for the snow-covered boulder on the right of the foreground and the snow to the left of the top of the waterfall, which were Zone IX.
When in the middle of any journey, it’s easy to lose sight of the destination. For photographers, that endpoint is the final print. The entire purpose of the Zone System is to produce a negative with as much information as possible based on our visualization of the scene.
Ansel Adams, also a highly trained pianist, was fond of comparing the negative to the score and the print to the performance. Sometimes his prints were fairly faithful to the real world and other times they departed wildly from reality approaching the surreal. With a good negative full of detail you, the photographer, have the raw material to play whatever performance you wish. Whether in the darkroom or on a computer, you won’t have a poorly exposed negative holding you back.
Now that we’ve covered Zone System metering, the next part in this series will focus on testing for the ideal personal film speed of individual shooters, and developing times based on individual equipment and technique.