The Zone System
The Zone System made popular by Ansel Adams nearly 70 years ago still plays an important part to a large number of photographers. It was developed to be used primarily with black and white negative film having in mind the chemical darkroom as part of the system. The Digital era has changed our approach to photography, what could be achieved in the chemical darkroom was a small fraction of what the electronic darkroom can output today. So, has Digital Photography made the Zone System obsolete? - No!
Many photographers use the Zone System along with digital photography. What is the value of the Zone System in the digital era?
Let us examine briefly the fundamentals of the Zone System.
Ansel Adams used the term - Visualization to explain the technique where the photographer creates a mental image of what he wants the end result to look like before he actually takes the picture. Once the visualized image is in the mind then the photographer uses the Zone System to get the data into the camera.
The Zone System uses any reflected light meter to achieve the exposure you want. The photographer using the Zone System previsualizes the final print and this functions is a powerful creative tool giving the photographer a lot of control over the final result.
In pre-Digital days, the amount of low or high contrast in a scene could be controlled by adjusting the amount of time the negative was developed. Today, Levels or Curves in the RAW software or in Photoshop are the tools of the Digital photographer offering far greater power and control.
Spot meters are not essential in the Zone System but they are more accurate and convenient than wide-angle meters. At times it is impossible to go close and read a specific part of a scene because of distance or obstacles.
IN SUMMARY - why should the digital photo grapher use the Zone System? The question arises because there are other faster ways of getting a perfect exposure for a particular scene.
1 . The Zone System teaches the photographer to have a mental picture of the scene as a finished product. This is a valuable skill to acquire.
2 . It teaches the photographer to select the best exposure so as to arrive at his previsualized image.
3 . Perhaps the most important reason is that it helps the photographer to think creatively, to slow down. To think about what he's doing.
How does it work in practice?
Understanding how the zone system works is very simple provided we first understand the basic principles. Before we can apply the system it is helpful to know the dynamic range of the camera we use. This means we want to know the number of stops our camera can register detail, from the shadows to the highlights. This can vary greatly.
So we are going to do a field test to obtain this important data.
Why is it necessary to know the dynamic range of the camera?
For the most part we want to capture beautiful images that contain texture and detail. The zone system divides the colour spectrum into 10 zones, from zone 0, recording pure black like velvet to zone 10, like brilliant white paper without any detail.
To apply the zone system we are interested in placing the important shadow area on Zone III, that means that Zone III is selected as the shadow area that will print full texture and detail - the exposure will be placed on that zone.
The exercise:
Ignoring the first shot count how many images recorded texture and detail?
To learn how many f-stops the camera we use records full texture and detail is the purpose of this exercise.
Select a wall or a large tree that is close to medium grey. Get close or use a zoom lens so that the viewfinder is filled with the subject. Use the camera meter or a hand-held meter and take a photograph at the reading given by the meter. This will be used as a starting point for what comes next.
Take four more photographs underexposed by one stop, two stops etc. Then go the other way and take four more shots overexposed by one stop, two stops, three stops, four stops.
The Canon 20D SLR can record at least six and a half stops with full texture and detail. Starting at Zone II and ending at Zone VII. If you wish to start with zone VIII counting backwards then zone III to zone VIII will record detail.
This means that when we select Zone II we know that this camera can record full detail all the way to at least Zone VII.
