This guide will explain the zone-focusing technique, not only how to use it, but how it works theoretically. Learn what zone focusing means and how to use it to take sharp photos.
You may have noticed that zone focusing is one of the most popular techniques in street photography. What is zone focusing, and how does this work? What can you do to improve your street photography or any other type of photography?
This is exactly what we’ll be talking about in today’s guide. We’ll take a look at zone focusing, define what a “zone” is, and see why it’s beneficial to your work.
Focus Theory: An Introduction
For zone focusing to be understood, you must first understand the science behind sharp images. It’s more complicated than just dialing the number that corresponds to your distance from the subject.
It is not accurate to think of these concepts as having a singular focus. Focus is always confined to a certain range or scale. This scale includes a range of values from defocus to sharp focus.
The focus zone is a scale that shows different degrees of sharpness at different distances. You can change the autofocus settings or the focus ring to adjust the zone’s center of focus. You can also change the shape and size of the zone in order to bring different subjects into or out of focus.
This is the basis of zone focusing. See what it means and how that may influence your future approach to focus!
The Zone of Acceptable Focus and the Focus Point
You should imagine that the focus in your image is a zone of varying intensity. The choice of your focus distance is more complex than you might think.
You can be confident that if you select a certain number from your focal distance scale, such as five meters, that the subject at that distance will be in sharp focus. What about subjects that are four or six meters away? You can determine your range of focus by extrapolating away from the chosen point of focus and examining the entire focus zone.
In the next section of this guide, we will discuss how to calculate the size of your focus area. Just know that there is a sharpness peak at the center of every shot. This point will be surrounded by an acceptable sharpness zone. As you move away from the focal point, the sharpness of this zone decreases. After a certain distance, the subject is no longer in focus.
The Focal Distance and Camera Settings
Rotating the focus ring will cause the center of focus in your zone to move this way or another. Your focus zone may also expand when you are focusing on an object that is far away. As you approach the minimum distance for your lens, this zone will begin to shrink.
It’s not immediately obvious how many other camera settings can also affect your ability to maintain focus.
Take a look below to understand what zone focusing is and why it’s about more than just dialing the right distance scale.
The Focal Length Factor
The focal distance of the lens can also influence the focus zone. All else equal, higher focal lengths produce smaller zones. You will only have a narrower range of focus when you use a long lens.
A wide angle provides a larger focus zone for the same distances. This makes it more flexible. It is for this reason that many street photographers relying on zone focusing choose wide-angle lenses because they are easier to use.
The Aperture: Its Special Function
aperture is the most versatile exposure control. It affects nearly all aspects of your photo to some extent. The aperture also controls depth of field. A larger aperture will produce shallow depth, while a smaller setting will create deeper depth.
What do the terms ‘deep depth-of-field and shallow depth-of-field really mean when it comes to zone focusing?
It’s really quite simple! Your focal point will be surrounded only by a small portion of the acceptable focus zone when you use a wide aperture. This is just another way to say that your image will have a very thin depth of focus. The depth of field in this context is the distance between two extremes of acceptable focus at opposite ends of the focus zone. field is simply another name for the focus zone!
A smaller aperture will add depth to your picture, thereby expanding your focus area. When you use a larger aperture, your focus zone will be smaller.
How Zone Focusing works in practice
Zone focusing becomes easy to understand once you have all of this information. The basic principle of zone focusing is to pre-focus your camera so that you can expect a large area of sharpness around your subject when you press the shutter.
You don’t have to follow your subject around if it moves. You can maintain sharpness in any situation as long as your subject stays within the area you’ve created.
You can increase the size of your focus area by using wide lenses and small aperture settings. If you do it right, this can let you shoot ‘from your hip’ and not have to confirm focus!
Use Zone Focus Accurately by Using Depth of Field Scale
Zone focus can be done in a scientific way, even though you could use the technique as described above. The following technique does not require a tape measure, though you are welcome to use one.
The depth-of-field scale is a feature that can be found on some modern cameras, but not all.
