If you have been dabbling in street photography, you will have noticed there is hardly any photography skill more lauded and venerated than the zone focusing technique. But what exactly is zone focusing, and how does it work? How can it help you take better pictures, whether in street photography or outside of that field?
That is precisely what we will be discussing today in this guide. Let’s take a good long look at how zone focusing works, what exactly a ‘zone’ is in the first place, and why it can be beneficial for your own work!
An Intro to Focus Theory
To understand zone focusing as a technique, it is necessary to first have a sound overview of the science behind how sharp photos come to life. Setting a correct focusing distance is about so much more than dialing in the number corresponding to the distance between you and your subject.
In fact, it is flawed to imagine a single point of focus when talking about these notions. Focus always exists within a range, or a scale, if you will. This scale ranges from complete defocus (blur) to pin-sharp focus and includes lots of intermediate values in between.
This scale of different degrees of focus across different distances is also called the focus zone. By manipulating the focus ring on your camera lens (or by changing autofocus settings), you are not just shifting the center point of focus within your zone. You are also able to change the size and shape of the zone to bring a different number and arrangement of subjects in or out of focus!
This principle forms one of the cornerstones behind the theory that defines zone focusing. Let’s see what that means and how it may affect how you approach focus in the future!
The Focus Point and the Zone of Acceptable Focus
As just described, you should really imagine the element of focus within your image as a cloud-like zone within with focus exists to varying degrees. Choosing your focus distance, then, is a much more complicated affair than it might seem at first glance.
When you choose a particular number on your focal distance scale – say, five meters – you can trust that subjects at that distance from you will be in focus. But what about those four or six meters away instead? To determine the range of acceptable focus that you can play with, it becomes necessary to extrapolate away from your chosen point of focus and examine the size and extent of your focus zone as a whole.
We will take a look at how to determine the dimensions of your focus zone further down below in this guide. For now, just understand that for every possible shot, there exists a focal point of peak sharpness surrounded by a zone of acceptable sharpness. The focal quality within this zone gradually decreases, moving farther away from the point. At a certain distance, subjects move out of focus entirely.
How Focal Distance Changes Depending on Camera Settings
It’s obvious that rotating the focus ring causes the center point of focus within your zone to shift this way or that way. You might also have noticed that your focus zone expands when focusing on a faraway object. Appropriately, it will shrink considerably as you reach the minimum focus distance of your lens.
What’s less self-evident is how many other camera settings equally affect your ease of maintaining focus.
Let’s take a look at these below to better understand the secret behind invoking zone focusing and why it is about so much more than dialing in the right number on your distance scale.
The Focal Length Factor
Like many other factors affecting the quality of your images, your focus zone is also influenced by the focal length of your lens. Higher focal lengths generally produce smaller zones, all else being equal. That is to say; you will have a much slimmer range of acceptable focus to play with when using a long lens.
Conversely, a wide-angle lens provides a large focus zone at the same distances, making it more flexible. This is why plenty of street photographers who rely on zone focusing prefer wide angle lenses for their greater ease of use.
The Aperture and Its Special Role
Out of all exposure controls, your aperture ring is by far one of the most versatile, affecting nearly every major aspect of your photograph to some degree. You might also know already that the aperture controls the depth of field, with larger apertures providing shallow depth and a smaller aperture setting generating deeper depth.
But what do terms like ‘deep depth of field’ and ‘shallow depth of field’ really mean in the context of zone focusing?
It’s actually quite simple! At a very wide aperture, your focal point is going to be surrounded by only a sliver of an acceptable focus zone. That’s but another way of saying that your picture is going to have a thin depth of field. In this sense, depth of field is nothing more than the distance (or depth) between the two extreme points of acceptable focus on opposite ends of your focus zone. The field in question is just another way of referring to the focus zone in the first place!
In other words, a smaller aperture adds depth to your image, expanding your focus zone. Your focus zone will shrink when using a wider aperture.
How Zone Focusing Works in Practice
Armed with all this knowledge, zone focusing is easy enough to understand. The core principle is to ‘pre-focus’ your camera such that a large zone of acceptable sharpness will form around where you expect your subject to be when you trip the shutter.
If your subject moves, you don’t necessarily need to chase it around to maintain focus. Just make sure that it stays within the zone you have created, and you should be able to maintain a sharp final result no matter what!
By using wide lenses with small aperture settings, you can maximize the extent of your focus field. Done right, that can allow you to fire ‘from the hip’ without having to confirm focus at all!
Accurately Using Zone Focus Using the Depth of Field Scale
While it is possible to practice this technique purely as described above, using generously wide apertures and focal length to your advantage, there is a more scientific approach to zone focus. No, no tape measure will be necessary for the following technique – though you’re welcome to use one just the same.
Zone focusing takes advantage of a feature not found on many modern camera lenses, namely the depth of field scale.
Ubiquitous on older, manual focus-era optics, a DOF scale lists the minimal and maximum focal distance for your chosen aperture setting in graphical form. In other words, it’s an easy look-up table for your depth of field (the size of your focus zone). If you really want to get into zone focusing the proper way, this is an indispensable tool.
DOF scales were never standardized. Different manufacturers have used different distances as their benchmarks for acceptable sharpness, and the visual design and layout of such scales also vary widely depending on the type of lens, camera, period of manufacture, and so on.
However, any DOF scale is far more useful than none at all. Try to track down a lens with this feature if you don’t have one already – preferably a wide angle lens – and see how much easier it can make the art of zone focusing all by itself!
A Word on Hyperfocal Distance And How to Use It in Zone Focusing
Every camera lens has its own so-called hyperfocal distance. With your camera set to focus at that specific distance, the extent of your focus zone will be at its absolute peak.
You can easily review and dial in the hyperfocal distance via the depth of field scale. That’s just one more reason why learning to read and using these scales is such an indispensable zone focusing skill, by the way!
To achieve your hyperfocal distance, select an appropriate aperture (i.e. as wide as the shot allows) and align the far end of your focus field with the infinity symbol on your focus ring. The other end of the DOF scale will now point to your hyperfocal distance. In other words, everything beyond that distance will now be in acceptable focus within your frame.
In the example above, the lens is set to its hyperfocal distance for f/8, which allows every subject farther than just beyond 5 meters away to be in good focus. As you can tell, the focus field would be much bigger at f/11 or f/16.
Some lenses or camera bodies that don’t have a full set of engraved scales on the lens barrel will make finding your hyperfocal distance easier by marking the setting with a dot on the focus ring. However, even without such additional aids, locking in the hyperfocal distance quickly becomes second nature to the seasoned street photographer.
Why Use Zone Focusing at All?
While having a solid grip on the technique and theory is all well and good, it’s important to ask yourself what you want to use zone focusing for in the first place.
In my opinion, you shouldn’t need to be too strict with this kind of introspection. Zone focusing is a base photography skill and one that can come in handy in countless fields. Especially as a beginner, there are very few reasons not to pick up something new, after all!
However, you might still be wondering how useful zone focus can be for the kind of photography that you yourself are practicing. In that case, let’s go over some common examples of where this technique can easily come in handy!
Combining Stealth and Speed in Street Photography
Street photography is where zone focus was invented, practiced, and first perfected by many of the old masters of the genre. It is also in street photography that the technique remains in very high regard to this day. Plenty of professional photographers consider zone focus to be one of the essential, irreplaceable skills one must learn if one hopes to become a serious picture-taker.
While that may be hyperbole in some sense, it is nonetheless true that zone focusing is immensely useful when shooting on the street.
Street photographers need to combine two qualities in their images that are often at odds with one another. First, they need to be able to shoot swiftly, often cranking out photos at only a moment’s notice and in quick succession.
Secondly and at the same time, these shots need to be well-composed and well-focused without attracting undue attention from the subject. Especially in more candid sub-genres of street photography, where alerting the subject to your presence at all is basically taboo, this makes for a very challenging balance to strike.
Zone focusing can make life a lot easier in this kind of situation. By managing your depth of field wisely and setting focus before you arrive on the scene, you can practically guarantee sharp images without having to ‘hunt’ for your subject excessively. And on top of that, zone focusing is the only method that can produce such reliable results whilst still being absolutely quiet. No whirring autofocus motors to catch anyone off-guard!
You will still need to think about the issue of fast-paced street photography composition, of course. But zone focus removes one huge burden from the equation, which should allow you to concentrate on that more effectively.
Shooting Incognito Without the Use of the Viewfinder
In many other photographic genres, such as wildlife photography, you may need to be cautious sometimes about how exactly you approach your subjects. Too much time spent behind the viewfinder adjusting peak focus can mean a lost opportunity and a missed shot.
Zone focusing mitigates that possibility by allowing you to pre focus while also controlling your depth of field directly. An experienced shooter can even do this without peering into the camera’s eyepiece at all!
Learning to compose by eye is a skill all of its own, and some find it very challenging. However, in combination with the zone focus technique, it’s a killer combo that can make you very quick on your feet as a professional photographer. This even becomes of use in some genres of portraiture, for example, where subjects often pose or act differently when they are aware they are being framed in someone’s viewfinder. Shooting ‘from the hip’ in such a case can give you unique, perfectly-timed shots you’d be hard-pressed to capture otherwise.
How Zone Focusing Helps You Understand The Science Behind Your Pictures
Even if you fall into none of the above categories, learning how to use zone focusing can teach you valuable lessons about the inner workings of your camera, its lens, and its optics.
Nothing can truly replace knowing your gear in my book. And for just about any photographer out there, understanding zone focusing adds a bit to that knowledge!
By taking the lessons learned from practicing zone focus, you can gain a more conscious command over things like depth of field, for instance. And such skills are useful for any type of photography, just about anywhere and at any time!
Using the Zone Focus Technique to Become a Better Photographer
Knowing what you have learned today about the elements of focal length, depth of field, focus fields, and how to read your lens scales, you’re well-equipped to go out and improve your skills on a practical level.
Zone focusing is but one of countless techniques that can help you improve the look and feel of your images. There is very little dogma here, so remember to change things up a bit to suit your own style.
It’s true, for example, that wider lenses make zone focusing generally much easier. Still, nobody is stopping you from using a longer focal length, as many successful street photographers have done over the years!
Likewise, feel free to combine zone focusing with semi-automatic and even automatic camera settings. It’s true that zone focusing started out as a manual focus technique specifically, but there’s no practical reason not to combine it with any of the countless advanced camera settings available today.
With that said, you now know all you need to in order to take your next steps. Try to implement some of what you’ve learned today in your next shoot and see how zone focus can make a difference in your photography!