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Autofocus, or auto focus, is the preferred solution for most photographic subjects over manual focus. AT skillful hands autofocus provides focusing more accurately, and, most importantly, faster than the average photographer. However, autofocus is far from being as simple as it might seem to a novice amateur photographer, and its correct use is very far from the point-and-shoot principle. There are a number of subtleties to learn if you want autofocus to stop taking on a life of its own and start doing what you want from him.

I highly recommend that you re-read the autofocus section of your camera's manual - it's one of the most helpful pages in the entire manual, and the information contained there should not be neglected. At a minimum, you should understand which controls are responsible for switching between different autofocus modes and choosing the focus point you need.

Most cameras have two main autofocus modes: single and tracking.

Single or single-frame autofocus (in Nikon cameras it is called Single Servo AF (S), and in Canon cameras - One-shot AF) is designed for shooting still scenes, such as, for example, most landscapes. When you press the shutter button halfway, the camera focuses on the subject within the pre-selected focus point, after which the focus is locked, allowing you to recompose the shot (without changing the distance to the subject, of course) before releasing the shutter.

It should be understood that in fact the lens does not focus on the object as such, but on a certain distances. Thus, if I let the camera focus on an object located at a distance of 5 meters from me, then all other objects that are 5 meters away from me, i.e. those lying in the focal plane will come out sharp, and as long as the focus is locked and the distance to the object does not change, I am free to rotate the camera to please the composition without fear of losing focus.

This method is good when the distance to the object being photographed is relatively large and measured at least in meters. At close distances, inevitable in macro photography, recomposing the frame, which entails a change in distance of just a couple of centimeters, can result in a noticeable focus shift relative to the object, which will be especially critical with a shallow depth of field.

Follower or continuous autofocus(Nikon - Continuous Servo AF (C), Canon - AI Servo AF) is indispensable when shooting moving objects, such as athletes or animals. As long as the shutter button remains half-pressed, autofocus continues to work continuously, keeping the subject in focus even as the distance between them and you changes. Focus lock naturally does not occur in this case, since the lenses of the objective are in constant motion, tracking the movement of the object.

Obviously, when using tracking autofocus, you cannot arbitrarily change the composition of the frame, because. if the active focusing point leaves the object being shot, then the focus will shift from the object to the background after the point. To lock focus in AF tracking mode, use back button focusing.

Intermediate or auto mode(AF-A or AI Focus AF), which itself decides whether to use single or tracking autofocus, does not inspire much confidence in me, since it is not always able to distinguish camera movement from subject movement.

Focus points

The number of focus points in modern cameras can reach fifty or even more. The abundance of focus points is, of course, nice, and sometimes useful, but even if your camera has a small number of points by modern standards (nine or eleven), you still have enough of them with your head.

When shooting stationary objects, I use only one single point, most often the central one. One point allows me to focus in the most precise way on the object I need, or even on a separate part of it, and then, after locking the focus, recompose the frame the way I want.

Auto focus point selection is handy when you're in a hurry, but keep in mind that the camera will usually try to focus on the subject closest to it or the area with the most contrast, which isn't always what you want. Autofocus cannot know which of the objects is the most important and requires unconditional sharpness, and which is secondary, and, therefore, may remain out of focus, and therefore do not be lazy to choose the focus point yourself, in case the camera's automation can not cope with this.

I only use auto focus point selection in the following situations:

• The object is moving very fast, and I simply do not have time to select points - the camera will do it much faster. This is also true when the photographer himself is moving, being, for example, on board a motor boat.
• A single subject stands out well against a relatively monotonous background, like a bird flying across the sky, and the autofocus has no chance of focusing on anything extraneous.
• All elements of the scene being filmed are at the same large distance from the camera, as, for example, when shooting with high mountain, and the difference between the distance to individual objects can be neglected.
• Shooting textures, when the surface being filmed is placed in the focal plane, i.e. strictly perpendicular to the optical axis of the lens.
• The camera is passed into the hands of a person who has no idea about autofocus.

In all other cases, I use a single focus point.

It should also be remembered that the shape of the focusing points in the camera's viewfinder only approximately indicates the true shape and dimensions of the autofocus sensors.

Focus or Shutter Priority

Focus Priority(focus priority) means that when the shutter button is pressed all the way down, the picture will be taken only if the subject is in focus. Otherwise, the shutter will not work.

If it is enabled trigger priority(release priority), then the picture will be taken whenever you press the button, regardless of whether focus is achieved or not.

Normally, the camera is factory-set to use Focus Priority in Single AF mode and Release Priority in Continuous AF mode, but you are free to change the priorities as you see fit.

Differences between contrast and phase detection autofocus

AT digital cameras The two most common autofocus systems are used: phase detection autofocus and contrast autofocus. Let's see how they differ from each other.

Contrast autofocus

Contrast autofocus is used in compact cameras, as well as in SLR cameras in Live View mode.

Contrast autofocus does not need any additional focus sensors and uses the camera's sensor directly to focus. The image coming from the sensor is analyzed by the camera processor for changes in contrast. When it becomes necessary to focus, the processor instructs the focus motor to slightly move the lens in an arbitrary direction. If the image contrast decreases, the direction is reversed. If the contrast has increased, the movement of the lenses continues in the original direction until the contrast begins to decrease again. At this point, autofocus returns the lens one step back, i.e. to the position in which the contrast was maximum, after which focusing is considered complete.

Due to the fact that contrast autofocus does not know how much and in which direction to move the focus point, it is forced to act by touch, focusing solely on the change in contrast, and, as a result, make a lot of unnecessary movements. That is why the main disadvantage of contrast autofocus is the slow focusing speed, which makes it completely unsuitable for shooting moving objects.

Of the advantages of contrast autofocus, it should be noted the simplicity of design, accuracy and the ability to focus almost anywhere in the frame.

Phase detection autofocus

Phase detection autofocus is used in reflex cameras both film and digital. In addition to the main mirror, which is necessary to direct the image to the viewfinder, the SLR camera is also equipped with a small additional mirror, which reflects part of the light onto the module phase detection autofocus. Each beam of light, passing through a special optical system consisting of a beam-splitting prism and microlenses, is divided into two beams, each of which is then directed directly to the autofocus sensors. In the case of precise focusing, the rays must fall on the sensors at a strictly defined distance from each other. If the distance between the beams is less than the reference, this indicates that the lens is focused closer than necessary (front focus), if the distance is greater, the lens is focused farther (back focus). The amount of shift tells you how far the lens is from perfect focus. Thus, phase autofocus immediately provides the processor with information about whether the subject is in focus, and if not, then where and how much the focusing lenses of the lens need to be shifted. This allows you to focus in one quick movement.

Phase detection autofocus sensors are linear and cross-shaped. Linear sensors, in turn, are divided into horizontal and vertical. Horizontal focus sensors are sensitive to vertical details (such as tree trunks), while vertical sensors are sensitive to horizontal details (such as the horizon line). Cross-shaped focusing sensors are versatile and sensitive to details oriented in any direction. You can find out which autofocus sensors are cross-shaped and which are linear, in the manual for your camera. The most sensitive sensor is always located in the center of the frame.

Focusing speed is the main advantage of phase detection autofocus, making it indispensable when shooting dynamic scenes. The main disadvantages are the complexity and bulkiness of the autofocus system, the need for careful alignment of all its components, lower accuracy compared to contrast autofocus, a limited number of focus points, and the inability to use classic phase detection autofocus in Live View mode.

Hybrid autofocus

Attempts to combine the advantages of phase detection and contrast autofocus have led to the emergence of hybrid systems, which are used in many mirrorless and some SLR cameras.

The essence of hybrid autofocus lies in the fact that phase sensors are integrated directly into the camera's matrix. Phase-detection autofocus provides an initial fast focusing, which is then corrected by analyzing the contrast of the image. At the same time, the entire system is very compact and does not require mechanical adjustment.

What else affects the accuracy of autofocus?

Aperture

Autofocus accuracy is directly dependent on lens aperture. The jumping aperture mechanism used in modern lenses means that metering and focusing are carried out at full open aperture, which automatically covers up to the selected value only immediately at the moment the shutter is released. The larger the maximum aperture of the lens, the more light will reach the autofocus sensors during focusing. Due to the fact that with a larger aperture, the light rays travel farther from the optical axis of the lens, they fall on the sensors at a large angle to each other, which makes it easier to determine the phase difference. The most accurate phase detection autofocus sensors are designed to work at apertures of f/2.8 and above, and any sensors stop working below f/8. In addition, a large aperture provides a shallow depth of field, which again improves focusing accuracy, as deviations from ideal focus become more obvious.

Focal length

The longer the focal length of the lens, the shallower the depth of field. It would seem that this should provide more precise work autofocus with telephoto lenses. Accuracy does increase, but at the same time, due to the vanishingly shallow depth of field, any autofocus miss is much more noticeable when using telephoto lenses, and in reality it is much more difficult to get into focus with a telephoto lens than with a lens that has a small focal length. On practice wide angle lenses much more tolerant of autofocus errors.

Detailing

Autofocus sensors need crisp, high-contrast detail on which to focus. So, if the object has clear contours or a relief texture, autofocus will do its job perfectly, but on flat, monotonous surfaces it will simply have nothing to catch on.

illumination

The brighter the scene is lit, the more accurate the autofocus works. When the light falls, the level of contrast to be assessed also decreases, making focusing very difficult. When the scene brightness is LV 1 (see "Light and exposure numbers"), autofocus works very badly, and at LV -2 and below, it is almost impossible to use autofocus and you have to focus exclusively manually.

Photographer

The main factor that limits the accuracy of autofocus is your ability to use it. No high-sensitivity sensors and ultra-fast focusing motors can replace the skill of a photographer. Without proper skill, even the most advanced autofocus system will constantly miss.

The most important thing about using autofocus is regular practice. A thoughtful approach to the operation of automation will allow you to focus quickly, accurately and not without excessive freethinking on the part of the camera.

Thank you for your attention!

Vasily A.

post scriptum

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When setting up the camera before shooting, along with shutter speed, aperture and ISO value, you need to set the focus mode.

Nikon cameras have many various options focus. You can select both modes and focus areas.

Focus modes:

AF-S (auto focus single)- In this focus mode, the camera starts to automatically focus when the shutter button is pressed halfway. In order to focus again, you need to release the button and press halfway again. This mode is suitable for static scenes.

AF-C (auto focus continuous)- This is the tracking focus mode. When the shutter button is pressed halfway, the camera constantly tries to focus. It monitors the change in composition or the movement of objects. It is very convenient to use this mode in dynamic scenes.

AF-A (auto focus automatic) is the automatic mode. The camera decides which focus mode to use. She chooses between AF-S or AF-C. Many people prefer to use this mode, and novice photographers may not even be aware of the existence of other focus modes.

M (MF - manual focusing) is manual focus. It turns on near the lens mount in cameras with a motor, and in the camera menu in cameras without a motor. This mode assumes manual focus by rotating the corresponding ring on the lens. For beginners, this focusing method may seem complicated, but professionals use it mostly. Manual focus mode is hallmark professional cameras from compacts (soap dishes). Auto focus does not work correctly in many situations, and in this case only manual adjustment can help.

The picture shows the focus point at which focus has been achieved.

Attention: manual mode provides the ability to focus on only one point.

Some Nikon cameras have a built-in rangefinder. It shows the photographer where to turn the focus ring to focus on a specific subject. Many older lenses that do not have auto focus have focus dials.

Any Nikon CZK camera has a pointing accuracy sensor. It looks like a green circle in the lower left corner of the viewfinder. When it lights up, it means that the sharpness is normal for the selected focus point. This indicator is a great help when working with older lenses, such as the Nikon 100mm F/2.8 Series E MF

Advanced cameras have fine focus adjustment - release priority and focus priority. It is available in AF-C mode.

The most commonly available settings in AF-C mode are:

1. FPS - frequency - for the camera, shutter release is more important than focus accuracy. It got the name release priority
2. FPS frequency + AF - shutter is priority for the camera, but focus is also taken into account.
3. Focus - Focusing is the top priority for the camera.

These priority settings determine how the camera will act. She can focus first and then take a picture, or take pictures, regardless of the quality of the focus. There is also an average value.

Note:

More budget Nikon models do not work in shutter priority mode ( release priority) in AF-S/AF-C modes. They operate in focus priority mode. Such cameras cannot quickly take a picture. Even though the shutter button is pressed all the way down, the camera will not take a picture until it is sure that the focus has been achieved correctly. This is a very serious flaw that occurs in Nikon D40, D40x, D3000, D60, D5000, D3100, D3200 amateur cameras.

To combat this inconvenience, you can shoot in manual focus mode (M). Some lenses have an M/(M/A) mode. It allows you to take instant pictures with manual focus adjustment.

Note 2:

Nikon professional cameras, shooting in AF-C mode, work with Release Priority. This mode allows you to take pictures by pressing the shutter button fully, whether the camera is in focus or not. Some cameras have this mode built in by default.

Live View (live view)

In this mode, focusing is much slower. The decrease in focusing speed reaches tens of times. Live View mode focuses on contrast. Some cameras have two focus modes in Live View. In the first, the camera focuses on contrast, as in amateur cameras. In the second, during focusing, the camera turns off Live View, focuses, takes a picture, and turns Live View back on.

Focus points and areas

Each camera has a different number of points and focus areas. For the focus itself, the module is responsible, which is located under the mirror of the camera. This module is engaged in the calculation of phase values ​​and gives commands for focusing. Usually, focusing modules have several points on which focusing is calculated. By 2012, Nikon cameras have modules with three, five, eleven, thirty-nine and fifty-one focus points. The ease of use of the camera and the accuracy of focusing depend on the number of points.

Working with focus points is carried out in the focus area mode - AF area mode.

• Auto (auto-area AF), automatic focusing on the nearest object that falls into the area of ​​the white rectangle. Focusing is performed on all available points.
• Dynamic focus (dynamic-area AF). It works on one point, but the setting takes into account the values ​​of a number of points standing near it.
• One point (Single Point AF). This type focusing is performed only on one point.
• Additional: multi-zone selection or 3D-tracking. These settings are not available in all chambers.

Single-point AF-S focusing

Advice:

In amateur and advanced cameras, there is a programmable button on which it is very convenient to set the focus mode switch for quick adjustment. On professional cameras, there is a special focus mode switch, which simplifies the work and makes it faster.

Note:

Some cameras can show which points have been focused. Focus points are marked with square markers. This feature is only available on professional (D200, D300) and full frame cameras. This mode is convenient because the focus points are scaled, so you can easily assess the quality of focusing. In amateur cameras, such a check can be performed by zooming in on the picture in playback mode and scrolling it with the selector to the desired point. Sometimes the camera does not show which point was in focus. In this case, you can use ViewNX. it comes with the camera. You can view the focus points in greater detail on the computer display.

Note:

Some Nikon cameras in automatic mode do not allow you to change the area and type of focus. Other modes allow you to customize everything the way you want.

Single point focus in AF-C mode

Looping focus points

This feature allows you to move the focus point in a circle. For example, if the rightmost point is selected, then to move it, you need to press the selector in the appropriate direction. This function allows you to quickly switch focus points.

Focus area width

Some cameras, such as the Nikon D200, allow you to expand the focus area by reducing the points. For example, a camera with 11 focus points switches to 7-point mode, but the focus area expands (creates 7 wide areas). In the viewfinder, the zones will visually appear wider, which can sometimes make focusing easier.

Fine-tuning (adjustment) focusing

It happens that the camera erroneously focuses when focusing behind the subject or in front of the subject. This is called back focus and front focus, respectively. To correct this shortcoming, some cameras have an adjustment. This setting is not available on all cameras. Nikon D300, D7000, D300s, D700, D3(s,x), D800(e), D4 have it.

"Dark" lenses and focusing

Almost all Nikon cameras use auto focus without problems only with lenses whose aperture is no darker than F / 5.6. You can read about it in the instructions. With darker lenses, autofocus may fail. For example, Tamron 28-300mm F / 3.5-6.3 XR Di VC LD Asph (IF) Macro will not work correctly when shooting with aperture F / 6.3. The use of teleconverters also affects autofocus. They lower the effective aperture value. Only a few models can work with dark lenses up to F8.0, such as the Nikon D4, although it does not guarantee accuracy at full aperture.

Cross-shaped and regular focus points

There is no noticeable difference between cruciform and regular focus points, but it is believed that cruciform ones do a better job with the task assigned to them.

Focus illumination

Nikon cameras have a special llama that helps you focus in low light conditions. The lamp simply illuminates the subjects, thereby helping the autofocus adjust the focus. Sometimes best result can be obtained using the red flash spotlight.

Note:

Many Nikon cameras do not turn on focus illuminator when single point focus mode is selected and no central point.

Nikon flagship cameras such as Dh, D2hs, D2h, D1, D1x, D2x, D2xs, D3s, D4, D3, D3x are not equipped with backlights at all.

Single-point focusing in AF-S mode

For those who do not understand everything?

If a given material hard to comprehend, just switch your camera to AF-A and set it to display a rectangular focus area. For the daily home use Auto mode will do the job just fine. Besides, in professional photography the use of precise settings is not always justified.

Conclusion:

Using manual focus settings helps you achieve the desired result faster. In order to understand the difference between the focus modes, you just need to try them all and see how they work and what they affect.

Based on materials from the site:

Acquaintance with photography most often begins with pictures of yourself, acquaintances, friends. Over time, the genre "repertoire" expands. You start photographing flowers in the garden, neighbor animals, nephews and nieces, friends' weddings. Products on the table, after all. Expanding the scope of the camera is a long process. But there is a fundamental skill that needs to be developed all the time. It's about getting high-quality, clear images.

Naturally, each of us has a shot of excellent content, which, in terms of a polite photographer, is "soft". Or, to put it as it is, blurry and fuzzy. But, given the uniqueness of the situation captured in the photo, the frame will remain in our collection. And, perhaps, its poor clarity only adds to the charm.

Focusing- the fundamental principle of photography since its inception. Back in the early 1900s, it was a separate "craft". However, in the 1960s, the legendary Leica introduced the first autofocus system to the public. This fundamentally changed the order of things. concept autofocus improved and today such functions are available in all cameras by default.

Modern digital SLR cameras (Digital single-lens reflex camera - DSLR), and not only them, have several auto focus modes. Trendsetters in this area are companies and. Other manufacturers are following the lead of the flagships. The names may differ depending on the brand, but the essence and principle of operation are the same. Therefore, consider the four main functions of autofocus in reflex Nikon cameras and Canon.

The photo above was taken with AF-S (Nikon) or One Shot (Canon) focusing. The center of attention is the eyes of the model. The camera is focused on them. The picture itself is recomposed in such a way as to leave a little space on the right side, in the direction of view.

Single Shot Mode (single focus mode)

Single focus- one of the oldest modes. At Canon it's called one shot. In Nikon models - AF-S. Regardless of the name, the essence of how autofocus works is identical. The mode is used for photographing static objects. Whether they are alive or not. Models on the set most of the time "freeze", providing ideal conditions to focus. The only rule for using the mode is that the subject should not move too fast (or much) in the frame.
To apply the mode, press the shutter button halfway (usually, the camera beeps and changes the display in the viewfinder). After that, change as you see fit. For example, if you need to focus on the model's eyes, focus on the model's eyes and then rotate the camera to position them on the left side of the image.
This mode is the most popular due to its simplicity. It works correctly in most cases.

Active or Continuous Focus Modes

Canon engineers called the next mode AI Servo. Their colleagues at Nikon preferred the acronym AF-C. The essence of the method is that the camera constantly monitors the movement of the initial focus point. And according to the change in position, changes the focus settings. This function is ideal for shooting moving subjects. For example, playing children, pets, vehicles - everything that is constantly in motion.

Auto Modes (automatic modes)

And finally, the last autofocus settings from the arsenal. It will be about AI Focus Canon and AF-A Nikon. Both modes leave the choice to the camera. best method focusing on parts of the image. The camera will either continuously track the subject if it moves, or switch to single mode when capturing a static frame.
Theoretically, before you click the shutter, you must select the most the best option autofocus. The author must indulge in long calculations about the specifics of the regimes. Not certainly in that way. The automatic mode in both brands works well and without further ado.
The author of this line has tested these setups by taking freeze-frames of moving objects. The result is very good. Cameras correctly select focus settings, giving a clear result. The statement is also true for stationary objects. Cameras determine the moment of cessation of movement and switch to "single mode".
On the other hand, it's still better to decide for yourself. Auto focus mode naturally has best qualities the modes mentioned above. But he absorbed all their shortcomings.

The image above was taken with a standard 85mm f/1.8 lens in manual focus mode. This type of shooting eliminates the risk of losing focus when changing the composition in automatic modes.

Thus, we have already managed to briefly get acquainted with the three main auto focus settings. Naturally, this is not full list. In particular, Nikon boasts excellent 3D autofocus capabilities. As well as other SLR cameras are equipped with " back button autofocus to help you focus on details more accurately. However, consideration of these topics is not the purpose of this article.

Manual Focus Mode (manual focus)

Now it's worth dwelling on the most rarely used focus mode. it Manual Focus- manual mode. The mere thought of abandoning automation inspires fear in those who have never used it.
When is manual mode necessary? In cases where you yourself choose a zone for a clearer display. This is creativity, the process of creating photographs and not fixing an event.
Thus, if the task is to shoot children, sports events, autofocus will be the most justified choice. But when shooting still life, architectural monuments, landscapes and other relatively static objects, manual focus opens up the horizons of creativity.

The simplest example is landscape photography. Any autofocus mode concentrates on a single subject. In our case, it is necessary to increase the number of focus points to the maximum. That is, to achieve a large depth of field. Automation only hurts here.
When shooting still lifes, photographers usually use a tripod. This is done in order to fix the camera and fully focus on finding (or creating) the perfect composition for the frame. In addition, a fixed camera facilitates the process of manual focusing.
There is another reason to use manual focus. And it was she who became the catalyst for the intention to write this article.

Take a close look at the photo above this line. The picture was taken using autofocus in One Shot/AF-S mode. Looks good. But if you zoom in, we notice that the eyes remained out of focus.
The author of these lines recently purchased a lens "". And, of course, I wanted to check what the levels of sharpness are with f / 1.8 aperture. Models served as subjects for shooting. Several shots were taken at f/1.8 in normal auto modes (AF-S/One).
Upon closer examination on the computer, it turned out that most of the frames are very "soft". That is, with fairly low levels of sharpness. It took time to understand where the error occurred and how to correct the situation.

Look at the illustration above. The focus node is located in the center of the viewfinder. This is despite the fact that I need a wider size when shooting a portrait.
The author did not have much experience shooting in shallow focus prior to this test. And now I got the opportunity to see the results of using this technique. Lenses with an aperture of f/1.8 have very, very shallow focus (depth of field). For example, when shooting a head with focus on the eyes, the nose is already blurry.
For testing, the model was filmed at 3/4 of its height. The distance to the photographer is about 2 meters. The focus point was placed on the girl.
The problem with most cameras is that although they have multiple focus points, all of these nodes are concentrated in the center of the viewfinder. And the choice of external (far from the center of coordinates) entails a significant change in the composition (rearrangement) of the frame.

The figure above shows what actually happens when changing the composition in search of focus points in automatic mode (AF-S/One). In short, the part of the image on which the initial focus was set falls out of the focus area.

When using lenses with f/16 aperture values, this problem is not particularly noticeable. But at f / 1.8 aperture, the focal plane shift automatically leads to “softening” of other important areas. An example is an illustration of the "soft eyes" of a model. The rearrangement of shots resulted in the point of focus moving to the background of the girl. That is, her back of the head, her hair fell into the spotlight and turned out to be sharp. But the eyes are the opposite.

There are probably no algorithms to solve this problem within the framework of “automatic modes”. You won't even notice the shift in the focal plane on a small camera monitor.
The only option that really helps is switching to manual focus mode. In this case, you can manually set the focus on the eyes of the model, other areas of the image that should be sharp.

Of course, when shooting models, there was a confluence of factors that exacerbated the problem.
Firstly, the shooting was carried out at aperture values ​​​​of f / 1.8. This always means critical sharpness values.
Secondly I shot from bottom to top. This always results in an increase in the focal plane shift when the frame is recomposed.
And finally, the problem of limited focus points. There are many reasons why modern SLR cameras do not place focal points at the edges of the viewfinder.
It's a paradox, but many "compacts" (mirrorless cameras), as well as micro cameras, have the ability to set the coordinates of focal nodes. In SLR cameras, alas, this technology is absent. So take advantage of autofocus where it works and feel free to switch to manual mode for precise focusing.

Like any automation, auto focus does not always work perfectly. Sometimes, the autofocus system can focus on the wrong part of the frame that you want to focus on in your photo.

Don't get us wrong, today's DSLRs and mirrorless cameras are capable of focusing faster than ever before. However, to create truly creative and artistic photographs, you need to adjust the focus yourself.

In what cases will autofocus not work properly?

Your camera may fail to focus automatically when there is not enough light or when shooting solid subjects, such as when photographing a brown dog in open field. AT this case the camera simply won't be able to determine the focus point.

In such situations, the lens will move back and forth, trying to fix at least on some point. If in this case, there is some kind of foreground object - a bush, a branch, etc., then, most likely, the camera will focus on it.

Moving subjects can be very problematic subjects for auto focusing. For such shooting, you need to make sure that you have selected correct mode focusing, only in this way there is a chance to make beautiful, clear and sharp images.

What focus modes should you use and when?

The first thing to decide is whether you want to use autofocus or switch to manual focus mode. There are several situations where manual focus is the best option. To make sure you're working in auto mode, look to see if the lens is set to AF and not MF.

Autofocus offers two different modes, one of which must be set on the camera. These are One-Shot AF (Canon) / Single-Servo AF (Nikon) and AI Servo AF (Canon) / Continuous-Servo AF (Nikon). One-Shot/Single-Servo is the best option for shooting still subjects. After the system focuses on the desired object, you can safely take your picture.

As the name suggests, in AI Servo AF / Continuous-Servo AF mode, the camera continuously focuses on the subject, this mode is more convenient for tracking the movement of the subject. In this case, you can take a picture at any point in the picture, even if the subject is out of focus. This is provided for faster and more productive work.

Many cameras offer another autofocus mode: AI Focus AF (Canon) or Auto AF (Nikon). In this mode, the camera automatically detects whether the subject is still or moving and switches to the appropriate mode accordingly.

Do not confuse the choice of autofocus mode with the choice of focus area, which can also be set automatically or manually.

What is the difference between autofocus mode and focus area?

The focus mode determines what how the lens will focus, and the autofocus area determines where the camera will focus. Focus areas may vary between camera models and manufacturers.

When working with a camera, the photographer has the opportunity to choose whether it will focus on one point, or on several. While looking through the viewfinder and holding the shutter button halfway, you will see how the camera focuses. When focusing on one point, you can move the point.

How many AF points should you use?

It all depends on what you are shooting. If you set the focus to multiple points, the camera automatically selects which ones to use to focus on the subject.

At the same time, if the subject is large enough, then you may not be satisfied with how the camera focuses. For example, when shooting a monument, the camera may focus on the legs of a statue, while you would like the focus to be on the face. In addition, in this case, there is a risk of focusing on foreground objects while the subject is in the background.

In the same time, auto focusing on multiple points may be more productive when shooting a subject against a solid background, for example, when photographing birds against a blue sky. The more autofocus points a camera has, the more accurately it will focus and better follow the subject as it moves through the frame. In other cases, it will be preferable to use multi-point focusing.

Of all available AF points, center point, provides the best accuracy. It is best to focus on this point, and then, after locking the focus, move the camera so as to compositionally create an attractive photograph.

When to use manual focus?

Manual focus may come in handy when the focal length remains the same. For example, when photographing a car race, you can automatically focus on the track, and then, when the car pulls up, switch to manual focus and, following the car, focus manually.

Manual focus is also the only option when the camera cannot concentrate on its own. Some lenses allow you to constantly adjust the camera's focus manually without having to switch from manual to automatic all the time.

How to focus with Live View

Live View focuses fine in manual mode. When switching to auto focus mode, don't expect miracles from your camera.

Auto focus

Auto mode in Live View may work differently with each camera model. Most cameras are capable of fast autofocus and a slower but more accurate mode with face detection.

Manual control

Live View helps with manual focusing, as you can use the screen to magnify part of the screen and fine-tune focus. This is especially useful for landscape and macro photography. The task of the photographer is to make a very fine adjustment, since the difference between sharp and clear can be significant.