To Zone, or Not to Zone: That May Be the Question

When I began photographing the landscape, the only option was using film, either black and white or color. When using black and white film, most of us used the Zone System or a derivation of it. Even those who cursed it as being too constrictive—it is not—or some kind of voodoo (again, it is not) were using this type of system in some way.

How does that have bearing on today’s photographer, who works most often using a digital workflow? It has great bearing! Simply because what we are trying to do is gain complete control over what we get in the original exposure so that we have the maximum information for printing.

That is not to say we have to use all of it in creating the final image. However, if the information is not there in the original exposure, it will not be usable in creating the final rendering, whether that is a print on your wall or if it spends its life captured on your hard drive.

The Zone System is not a photographic religious dogma that must be obeyed without question and at any cost. My purpose here is to, at least partially—and I hope in total—remove the mystery created by many people who don’t have a clear understanding of it and so cannot make a cogent statement about it. Many also make it so complicated that the uninitiated flee in terror. The Zone System is simply a method of determining the most effective camera exposure and film processing combination so you get the information you want onto the film negative, almost always black and white film, which will then be easily printed onto a piece of photographic paper. A side note here: recognizing that most photographers no longer maintain a wet, or traditional, darkroom, the information given here will be useful to anyone using traditional film, even when the film will be scanned for printing. There will also be a definite crossover for the digital photographer.

Many years ago, I had a chance encounter with a man who explained using the Zone System in such simple terms that I immediately, almost instinctively, understood the basics of using it to make the kinds of photographs I had dreamed of creating but didn’t have the technical knowledge to achieve. Frankly, in reading a lot of the literature about using it and seeing numerous YouTube videos on the subject, it has become apparent that many of the people trying to teach it don’t have a solid grasp of it either. In this post, which will come in several episodes, I will attempt to explain it clearly and in the simplest terms.

First, the purpose of using the Zone System, as invented by the great American landscape artist Ansel Adams and his cohort Fred Archer, is to be able to print an image onto a piece of photographic paper that contains the impact seen in the original scene. This is done using two steps that are absolutely interlocked and interdependent. The first part of the equation, which is the foundation, is film exposure. If the exposure of the film is wrong, it will cause everything else in the image to be anywhere from difficult to print to impossible to render. Remember that, in the time period when this system was devised, there was no such thing as a digital camera, only film. There was no immediate review or histogram to check, so the photographer had to be accurate in exposure, and the film had to be properly processed since the end result was always a black and white photographic print.

In the simplest possible terms, when using black and white film for purposes of the Zone System, all shadow detail is based on film exposure only, and highlights are determined by film processing. To clarify, detail can only be placed in the shadow areas by exposure. That is because, once the shadows are fully developed, they will not gain usable detail by adding any reasonable amount of time to the film's development. Once the exposure has taken place, shadow detail is set; no amount of additional development will add shadow detail. Additionally, full development of the shadow areas happens pretty quickly—usually by about three minutes of development once an active developer solution is in contact with the film. For that reason, we always base exposure on the darkest areas where we want printable detail and tonal separation. Highlights, on the other hand, will continue to develop as long as the film is in contact with an active developer solution. We can control how much negative contrast there is simply by changing the amount of time the film is in contact with an active developer solution. More on film processing later.

The first thing we must account for is the film’s exposure. Let me begin by stating that all conventional black and white film exposure and ASA rating is based on shadow detail. This excludes so-called chromogenic black and white films since those are essentially color films without color dyes, and the chemical process is completely different from that of conventional black and white film. Without a long explanation about how ASA is determined, let me state simply that it is based on the minimum amount of light it takes to form an exposure on a piece of film under laboratory conditions, not field conditions. Below that level, there will be no measurable change in the film’s density even though it was exposed to light. A cautionary note: the ASA of black and white film is almost always overstated by at least one stop of light. For that reason, I expose the film I use most often, Kodak T-Max 400, at an ASA of 200.

The first step in using the Zone System for creating a very printable negative is finding the darkest area in the photograph that will be useful to you in creating your final image. For that reason, I almost always seek out that darkest area, point my spot meter at it, and take a reading.

Here is an example of an image I am working on right now. The film is T-Max 400, exposed at an ASA of 200. The area selected for exposure was placed on Zone IV.

The darkest and lowest metered area, the shadows, informs me of what my basic exposure will be. The difference between the amount of light reflecting from the darkest important shadow area and the light reflecting from the most brilliant useful highlight is called the Scene Brightness Range. The Scene Brightness Range (the difference between the darkest area where I want printable detail and the area with the most brilliant highlight detail) helps to determine how the film will be processed. In this case, the most brilliant important highlight area, where light was reflecting off the rock in the foreground, and the area of deepest shadow was six stops. I determined that the brilliance of the water at the end of the lake wasn’t of particular concern since it is a direct reflection of the open sky, and there was no detail there that I needed to record on the film.

Conventional photographic paper can only print a tonal range of 4–5 stops. If the Scene Brightness Range of the area portrayed exceeds 5 stops of light, an adjustment will have to be made in the film’s processing, or there will be areas that are very bright where detail cannot physically be printed. In this case, since the difference between the darkest important shadow and the most brilliant important highlight was six stops, I reduced the film’s development by an amount that would compress the tones of the scene into a 4 ½–5 stop range.

Here is a representation of the Zone Scale. Notice that the bracket of paper’s printable dynamic range only goes from Zone IV to Zone VIII. Detail in Zone IX will be very difficult, or even impossible, to print. In observing this, it should be noted that even though film is capable of reproducing each step of this scale, photographic papers are not capable of printing them. I would also note that in a digital workspace, the capabilities of a printer, like my Epson wide format printer, are very different from a darkroom printing paper.

As previously stated, highlight detail is controlled in film processing, and that will be covered in a subsequent column.

The photographic paper I print on at this time is Ilford Fiber Based (FB) paper. I use a glossy or F surface paper which, when air-dried, has a very nice sheen to it, not an objectionable glossy finish: Ilford Fiber Based Paper.