Camera Focus Modes explained for Beginners

Michael • updated June 30, 2022 • 8 min read

Camera Focus Modes Explained for Beginners

What good is the best camera if the picture you take is still blurry? And not because the gear is broken, but because people don’t know how to use the focus on their camera. That will change, after you read this article

Where the image’s main point of interest is also where it is sharpest. Think of it as a thin curtain that covers the whole room at a certain distance from the camera lens.

With focus you can create the sharpness in any way you want. It should be put where the viewer’s eyes are meant to go when they look at the picture later.

This means that the focus isn’t the only thing that makes a picture technically perfect. It also makes a big difference in how the photo looks.

It helps us figure out what’s important in a picture and where the eye will be drawn. And fade out things that aren’t important or are distracting.

From a technical standpoint, we show you how does Camera Focus work and everything you need to know about focus modes.

Camera Focus Modes explained, learn about the huge potential that modern mirrorless systems cameras with their advanced focus options.


 

Introduction to Camera Technique

Before we get into how to focus and common techniques, you should know a few basic words and steps.

To learn how to take pictures, you need to know at least these things. It all starts with how the camera finds the focus on its own. And to be able to focus in a tiny amount of time.

Single focus point, graphic, camera focus explained
Singe Focus Point

Camera Focus Modes Explained

As I said, you have to pick a plane of focus in space when you take photos. This is always in line with the lens and goes once across the whole photo. Depending on the aperture, the sharpness drops off faster or slower from there, depending on how wide the aperture is. But this razor-sharp point is really only sharp at one hundred percent.

By moving the focus on the lens, you can move the plane of sharpness back and forth. This is because the lenses inside the lens also move. The focus distance controls how far away from the lens the plane of focus is.

This is often shown on the lens with a scale. It can be changed by turning the focus ring in hand. Or, the built-in motor is used to move the focus lenses. This is called autofocus.

But autofocus is more than that. How does the lens even know how far to move the inner lenses to focus so that the desired spot looks sharp at the end?

Phase and Contrast Autofocus

The lens has a motor that lets it focus, but it needs to be told to move to a certain distance by the camera. The camera uses contrast as a guide to figure out how far away this point is from the “aimed” point in the viewfinder.

Zone focus points, graphic, camera focus explained
Zone focus points

Phase Detection Focus

Unless you use Live View to focus, classic DSLR cameras use phase-detection autofocus. I don’t want to talk too much about how things work. At this point, I think it’s most important to know that this method usually works through a focus module. This works out the focus distance without using the sensor. Because of this, the later image is not always the same, even if the focus is perfect. This is why for example Sigma lenses must be calibrated first.

Another problem is that there aren’t usually that many autofocus fields, and the ones that are there are usually in the middle of the picture.

Contrast Autofocus

In addition to phase autofocus, mirrorless cameras can also use contrast autofocus. When an area of an image is sharp, it just means that the pixels next to it have very high contrast.

And the camera looks at this difference at the desired location. In simple terms, the lens then focuses until it finds a place with 100 percent sharpness contrast.

One thing to keep in mind is that most of the focus happens at the sensor level. As the camera focuses, the processor looks at the image for sharp spots all the time.

The benefit is that this can happen almost anywhere on the surface of the sensor. Faces can also be found with a little bit of computer magic.

Not only are there more options, but you also get the same level of sharpness in the picture that you saw when you took it.

Unlike phase autofocus, almost everything happens right on the sensor. No separate unit anymore.

How to get the Autofocus to work?

The button on your camera that lets you open the shutter always has two stages. If you press it halfway, it turns on the autofocus. The picture is only taken at level 2 when you press it all the way down. This has been the factory setting for decades, and it still is.

In the meantime, though, there are better ways to do things. For example, it is usually best to separate the focus from the shutter release and set up extra buttons for eye autofocus or object tracking. We’ll talk about that soon.

Where to actually Focus?

The focus determines what the viewer will look at later. The focus is therefore an important creative tool for telling the story of your photo.

In reportage photography, for example, there are no rules. You focus on what matters at that moment. With a small aperture value like F1.4, at close range, the rest of the photo just fades out.

For portraits, the camera’s focus should be perfectly on the model’s eye. People also look other people in the eye during real encounters. T

his is something very human, which is why you want to look people in the eyes first. If this is not possible because of a blur, the portrait will seem wrong somehow.

If your model is slightly turned in and the eyes are not on one level, you should always focus on the front eye. If the back eye is a tad blurrier, it’s not as tragic as the other way around.

With landscapes, on the other hand, you want everything to be sharp. That’s why closed apertures are usually used for a high depth of field. To show everything important sharp from front to back, the hyperfocal distance is usually set as the focus.

Note that there are still limits to focus. For example, every lens is specified with a close focus limit. If you want to focus closer than this, it will not work. If you still want to see the image larger, you should check out my post on macro photography.

Now that we’ve got these things out of the way, let’s get down to the basics.

Which Focus Area or Zone should you choose?

When it comes to autofocus, we need to get back in charge, just like we do when taking photos in general. Most cameras are set to let you focus anywhere in the viewfinder right out of the box. 

Most of the time, the camera just focuses on whatever is closest to it. But there’s a problem if you want to pay attention to something far away. So, we now make it so the camera can’t choose a focus point on its own or can only choose from a certain area.

Note: Please check your camera’s manual to learn how to use all of the settings mentioned in this article.

Using the Single Spot Focus

Focusing on a single focus field, like the one in the middle, gives you the most accuracy. Even with phase autofocus, the central fields are often the most reliable because they usually have the best cross-type sensors. You can also change the size of the focus field on a camera that doesn’t have a mirror. The more precise, the smaller.

Advantage
The good thing about this method is that you can really zero in on what you want. One problem is that the camera will start pumping if it can’t get the focus right at this point (for example, because there isn’t enough contrast). We have told it that it can’t just use the focus field next to it instead.

Still, this doesn’t happen very often, and the single focus field is still the best choice for most situations. Tips, I’ll show you what you can do with focus pumps.

  • The single spot is best when you need to be precise and the subject is still.

Select Zone Focus

This is called a zone focus, as the camera for example activates focus field only in the right half of the picturee. In other words, you restrict the camera’s movement while still giving it some room to move.

Advantage
Depending on the camera, these areas are called the wide, broad, center, and so on. Most of the time, the square brackets [ ] show where the zones are. This way the camera can follow objects better than we could with a single focus area.

The zone focus can help you, especially when shooting athletes, running animals, or videos. If you’re just using eye-autofocus or object tracking, a zone focus also makes sense. We come back to this later.

  • Zone focus can better for things that are moving.

AF-S, AF-C or Manual Focus Mode?

Now that we’ve told the camera where to focus, we’re done. In the next section, we will talk about how the focus acts. Even though there are now some “smart” ways to do it, depending on who makes the camera, it always comes down to:

AF-S Focus Mode Setting

Autofocus Single, also called “One Shot” by Canon users, does exactly what it says: it only focuses once per photo. When you press the shutter button halfway, the camera focuses on that point.

As long as you keep your finger on the shutter button in this way, the focus distance will stay the same for a short time. After you take the picture, the game starts over from the beginning.

  • AF-S is usually used when the subject is not moving.

AF-C Focus Mode Setting

Continuous focusing is what Autofocus Continous (or AI Servo in the case of Canon) means. When the shutter button is halfway pressed, the camera doesn’t just look for the focus point once. As long as it is tapped, the distance is measured several times per second and the focus is tracked continuously.

This makes it possible to keep track of things like cars. During this time, the only thing that matters is that the chosen focus point stays on the object.

  • Most of the time, AF-C is used when the subject is moving.

Manual Focus Mode

If you want to use manual focus, you have to turn the lens ring by hand. If there is an autofocus motor in the lens, it won’t move. In newer lenses, it only does this so that the electronic signals from the ring can be changed (focus by wire).

This type of focus is especially important for retro lenses that don’t have an AF motor. Also, even with an autofocus lens, there are many times when it’s better to focus manually.

For example, when using a tripod to take pictures of landscapes or products that don’t move. Or when the autofocus doesn’t work in backlighting, low light situations, or extreme close-up shots.

Previous Focus Mode Techniques

Now you know that autofocus is made up of a random AF area (or zone focus) and a command to focus on it for once or continuously. From this have come the following basic techniques:

Manual selecting the Focus Point

  • AF Field: Single Spot
  • Mode: AF-C or AF-S

The way to begin is to move the focus point to where you want the sharpness to be later in the picture. To do this, look through the camera’s viewfinder and tilt it until the image looks right.

For example, if the model’s eye is in the right half of the picture, you just move the focus point to one of the right focus fields above the eye. Then you just have to press the shutter button all the way down.

The good thing about this method is that there is almost no lag, so there is no room for error. In AF-C mode, you can also follow moving people.

To do this, just hold down the shutter release button and move the camera so that the focus field stays on the person. Then, when the time is right, you press the button all the way down.

Focus and Recompose

  • AF Area to Single Spot
  • Mode to AF-S.

If you have to change the focus field before every shot, it can sometimes get in the way of your work. So, with this method, you just leave it in the middle of the picture.

Most of the time, the advantage of centered focus fields is that they are cross-sensors, which are better at detecting differences. First, the focus point is put in the middle of the person’s eye, and then the shutter release button is pressed halfway and the you finally take the shot.

The picture can then be moved around while the shutter release button is still half-pressed. This is important because we want to use our own design, not just take photos from the center. If the picture looks good, just press the button all the way down.

The problem is that when you recompose the photo, you often shake a bit because of your own movement. Or just often, panning way too far.

This makes the stored focus distance move a little, which makes the image blurry, especially when the aperture is small. Before you make this your standard, have some practice.

The fact that the focus is completely changed before each photo is both a plus and a minus. This lets you make sure that every picture has the same sharpness. This is useful even if the camera itself is out of focus.

Focus and Recompose can only be used with AF-S. If you accidentally choose AF-C, when you half-press the shutter button, the camera will focus on the background as soon as you move the focus area away from the person to recompose the photo.

Modern Focus Mode Techniques in Mirrorless System Camera

You should pay a little extra attention to the following techniques because they are my absolute favorites. They have made capturing images much easier.

Eye Autofocus

  • Turn on autofocus for the eyes in the menu.
  • Mode: AF-C

If I had to give you just one reason to switch to a modern mirrorless system camera, I would say that the eye-autofocus is a major reason.

Eye-autofocus has changed everything about how I take pictures. No more “focus and recompose” panning and no more “focus point moving.” You can concentrate on your content and composition of the photo. 

As was already said, it comes down to the camera’s ability to actively analyze the image in the live viewfinder. This means that it can also tell who someone is by looking at their eyes and faces.

Once the eye is found, the camera automatically focuses on it (usually its the person closest to the camera on case of Sony).

If your camera can do this, make sure to try it. With Fujifilm, Canon, Nikon, and especially Sony’s mid-range to high-end mirrorless cameras, you can usually use them without worry. Some cameras now can even recognize animal eyes.

In AF-C mode, you can then just hold the shutter release button halfway down. This makes the focus track the eye again and again, even if you move.

Face autofocus and eye-autofocus are not the same. What you want is eye autofocus, which gives you more accurate results.

Object AF Tracking

  • Autofocus Lock / Enable settings AF-C
  • Mode AF-C

Not only eyes can be detected by analyzing the image content while focusing. Almost any other object can be focused on once and then tracked automatically.

A specific structure, such as a car license plate or a T-shirt print, can be detected here. The focus is now instructed to keep this element or pixel arrangement in view. The focus is then magically tracked in AF-C.

  • Object tracking is similar to eye autofocus, but for everything else.

As a result, the camera automatically tracks the athlete, race car, or carriage, for example. It does not, however, perform as well as the eye-autofocus. The camera occasionally loses focus on the object. But it already works very well and has a lot of potential.


Focus Mode Tips

  • If the autofocus fails to focus, it simply fails to find a contrast. This is common when you want to focus on uniformly colored areas with no patterns, for example. Instead, try to direct the focus field to structures at all times.
  • Avoid to goback  to the menu every time you need to change the focus. Use the Quick menu (Fn) or a separate custom button for the most important functions, such as field selection.
  • The quality of autofocus is only as good as the equipment. If you have ongoing issues, consider purchasing a faster camera and lens.
  • Consider a faster camera and lens. Better camera focus algorithms and processing power are important, but so is the speed of the lens’s AF motor.
  • Most of the time, lenses from your own manufacturer provide faster autofocus. Third-party lenses are sometimes slower, especially when used with an adapter.
  • Manually focus (or use the Back button) on a location where a person will soon be. Assume your model leaps over a puddle. Then, manually adjust the focus to the distance of the puddle. When the model enters the focused area, simply press the shutter button.
  • Check that the lenses on your DSLR camera are properly calibrated for phase autofocus. There is no sensor-level control in this case, as there is in contrast autofocus.
  • In low light, the focus frequently struggles, resulting in pumping. Manual focus can then be used with slow subjects. A flash with an appropriate AF assist light should be used for reportage. In the dark, AF-C on my Sony performs better than AF-S. Experiment with what works best for your camera in low light.
  • Create a button with the function of returning the focus point to the center. Allow the camera to remember one focus area for portraits and another for landscapes.

Practice. It’s the routine that allows you to take sharp photos even at F1.4 or f/1.8 especially with techniques like focus and recompose. 

Frequently asked Questions


How does the auto focus work?

Automatic focus is best compared to your eye. Your camera, like your eye, uses contrast in the image to make everything sharp. When the contrast difference reaches its maximum, the camera recognizes that the image is in focus.

Based on a few focus points, your camera determines which area to focus on. The total number of focus points is determined by the make and model of your camera.

Just got my first DSLR camera, how do I focus?

If you put your finger on the shutter button, you’ll notice that you can press it halfway and all the way down. If you look through the viewfinder and press the shutter button halfway, your camera will focus with autofocus. You’ll usually hear a beeping sound when it focuses, and you’ll also see it directly in the image, focusing on a specific area in the photo.

What is the focal point of a photograph?

The focus determines how far away the plane of sharpness in the image is. This is a very thin area with perfect sharpness due to appropriate contrasts. You will learn how to hit it easily and correctly in this article.

What happens in the lens when focusing?

The autofocus motor moves individual lenses within the lens to achieve the proper distance setting. This information is received by the lens from the camera, which has previously determined the distance.

Which focal point should I use?

In most cases, a single spot focus field is recommended. This provides the greatest precision. Specific autofocus zones, especially for moving objects, make sense in the scenarios mentioned above.

In which focus mode should I set my camera?

The AF-S mode is recommended for stationary objects. Switch to AF-C mode as soon as you want to track moving objects.


For more camera type specific focus mode information look also at:

Sony – Autofocus modes
Canon – Autofocus modes
Nikon – Autofocus modes

What do you thins about “Camera Focus Modes Explained”  – let us know in the comments!

By Furoore team member Michael
Furoore Team is here to assist you in capturing the most significant moments in your life. To create exciting photographs, discover photography guides, find unique photo ideas, and limitless image inspiration.

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