Choosing the perfect autofocus mode can seem tough and even overwhelming (especially if you’re a beginner). But if you get the AF mode wrong, then you risk capturing consistently blurry shots.
Fortunately, there are only a few autofocus modes you need to keep in mind – and each of these modes has its own set of ideal scenarios. In this article, I explore these AF settings, and I explain precisely when you should use (or avoid) different options.
So if you’re ready to start consistently nailing focus in your photos, then let’s dive right in!
The three focus modes you should know
Most cameras are equipped with three key focus modes:
- AF-S, also known as One Shot
- AF-C, also known as AI Servo
- Manual (sometimes abbreviated as M)
Note that some cameras include an additional focus mode, known as AI Focus or AF-A. But because AI focus is so finicky and ineffective, I don’t use it myself, and I don’t recommend you use it, either. Instead, stick to the modes I’ve shared above.
So how do each of these key focus modes work? Assuming that you use the shutter button to activate focusing:
When set to AF-S, your camera will acquire focus as soon as you half-press the shutter button. That point of focus will then lock until you let go of the shutter button.
When set to AF-C, your camera will begin to acquire focus as soon as you half-press the shutter button. But it will continue to refocus as your subject moves (or as your camera moves). Depending on the AF area mode that you choose, a camera in AF-C may track a subject as it moves through the frame, it may continuously acquire focus at the center of the image, or it may do something else entirely (such as focus on the subject’s eye).
Finally, when set to manually focus, your camera won’t focus at all. You’ll have to do all the focusing work via the focus ring on your lens, which can be slow but is also very precise.
To recap:
- AF-S focuses and locks.
- AF-C focuses and keeps focusing, potentially even tracking a subject as they move.
- Manual leaves control over focus to you, the photographer.
How to choose the perfect focus mode for each scenario
So when should you use each of the focus modes discussed above? It depends on the scenario:
1. Use AF-S mode to photograph stationary subjects
AF-S focus mode is my go-to, and the mode I use most frequently. When first pulling out my camera, AF-S is my default pick. It has so many applications, from landscape photography to street photography to portraiture and more – and if you’re more of a still photographer (i.e., not an action/sports/wildlife shooter), I recommend you use it constantly.
Basically, whenever you’re shooting a non-moving subject, AF-S is a good choice. You can set the focus point to the center of the frame, half-press the shutter button to lock focus, and then compose the shot however you like. (This is often referred to as the focus and recompose technique.)
For instance, if you’re photographing a street scene, you can focus on a prominent element, such as an interesting poster. Then you can carefully compose the scene. As soon as all the elements come together (e.g., a person walks through the frame in just the right place), you can take the shot!
I’m also a fan of using AF-S for handheld landscape photography. I’ll often find myself wanting to put elements off-center, so I’ll lock focus in AF-S, then shift the composition slightly. Then, when I take the shot, it looks exactly the way I envisioned.
Bottom line: AF-S is an extremely useful mode, and it’s the setting I recommend you use whenever you’re shooting a motionless (or nearly motionless) scene.
2. Use AF-C mode to photograph action
AF-C mode allows you to focus and refocus, or focus and track a subject as it moves throughout the frame, which is what makes it such a great option for action photography.
This refocusing capability is invaluable when shooting sports, where players rarely stay still long enough to allow for easy focusing. And AF-C mode is great for wildlife and bird photography because you’re frequently faced with fast-moving subjects at high magnifications. (Many bird and wildlife shooters use AF-C mode almost exclusively; it’s the only way to keep feeding shorebirds, flying songbirds, running gazelle, and charging elephants in focus!)
You’ll probably even want to use AF-C mode if you’re an insect photographer, assuming you’re shooting an active subject such as a butterfly.
Pet, portrait, and street photographers can also profit from using AF-C a lot of the time, though I recommend switching between AF-C and AF-S depending on the situation. A sleeping dog certainly won’t require AF-C, but a jumping dog absolutely will!
You should also be aware that AF-C often offers quite a few useful AF Area modes (which are mostly used for tracking). These allow you to specify whether a subject should be tracked at a single autofocus point, by nearby surrounding points, or even across the entire frame.
So just remember: If you’re hoping to capture the action, pick AF-C.
3. Use manual focus to handle tricky situations
Manual focus is often an AF mode of last resort, and it’s the setting you should try when AF-S and AF-C fail. As I explained in a previous section, manual focus is extremely precise – after all, it lets you adjust the point of focus using the ring on your lens – but it’s also very slow. You often need to move the focus ring back until you get a sharp result, so it doesn’t work great when trying to photograph athletes or birds in flight.
That said, manual focus is the only mode that is consistently accurate – no matter the lighting, and no matter the size or color of your subject. You see, there are some situations where AF-C and AF-S just don’t work well:
- When the light is low
- When your subject is heavily backlit
- When your subject includes very little contrast
- When you’re working at very high magnifications
Whenever you’re confronted by these situations, your autofocus may hunt like crazy, and if you keep trying to nail focus using AF, you may end up with a slew of blurry photos.
Switch to manual focus, however, and your photoshoot will be smooth – albeit slow – sailing.
I do all of my macro photography in manual focus mode. My lenses just can’t handle focusing at such close distances, so if I were to use AF-C or AF-S, my camera would likely just try to focus forever.
I also do still life photography while focusing manually because I often work in dim light (with a couple of flashes). And I’ve even used manual focus when photographing backlit birds because my AF-S and AF-C modes struggle to lock onto silhouettes.
Note that manual focus can also be used to gain finer control over your point of focus. Many landscape photographers use manual focus mode for this very reason: It allows them to choose a point of focus that maximizes the depth of field, and it even allows for precise focus stacking.
So don’t think that manual focus is only designed for a few specialized genres of photography! It can be useful in a number of different situations, and it pays to practice frequently. That way, next time you’re in a situation where your autofocus isn’t working, you can quickly switch over to manual and nail the shot.
How to choose the perfect focus mode: final words
Now that you’ve finished this article, you know that choosing a focus mode doesn’t have to be overwhelming! Just follow the advice above, and pick the right settings for the right situation.
Also, don’t be afraid to use manual focus; it may be slow, but it’s highly effective!
Now over to you:
Which focus mode is your favorite? And how do plan to pick your focus modes? Let me know in the comments below!
