Apply digital filters for autofocus. What you need to know about focus. Manual focus. Thin setting of autofocus

How does autofocus work in a smartphone? What type of autofocus works better? Pros and cons of laser, phase and contrasting AF. What is so good Dual-Pixel?

How does autofocus work in a smartphone? There is no simple answer to this question. It is necessary to deal with each type of autofocus, study the features of a specific focus technology. Only after that you can do at least some conclusions. Therefore, now we will talk about the varieties of automatic focus technologies, and the advantages and disadvantages of each of them.

What is focus and autofocus camera

Everything is simple: the lens lens refracts the rays and collects all the light at one point - focus. And if at this point there is a matrix sensor, the frame is obtained more detailed and high-quality. Naturally, all photographers are used by this physical phenomenon. They put "in the focus" any part of the frame, set up the lens manually and focus the attention of the viewer in the front or in the background, the main object or the secondary part. The rest of the picture will be blurred.

Well, novice photographers can use the automatic focus system when the automation captures "in the focus" one or more objects in the frame, controlling and lens, and the matrix. And these objects (or object) are obtained as much as sharp and detailed. And no skill and feelings of the frame here are no longer needed.

It is probably why the digital photo has become more popular than film-paper version of art. After all, autofocus in the phone or cheap camera allows you to make a detailed picture without extra effort. The whole process comes down to a simple rule: "Nadd and click".

Varieties of autofocus and basic principles of their work

The camera lens focuses the rays reflected from the subject located in space in front of the lens. When focus hovering, the camera is focused on the distance to the object and the intensity of the luminescence emanating from it. Today there are two varieties of automatic focus modes:

The active version is based on the distance measurement using a rangeference locator.
Passive option - it works with a light beam, measuring its intensity.

The first (active) mode uses laser infrared or ultrasound radiation at a certain speed of propagation of the wave in the air. The emitter module emits a directional flow that is reflected from the object and is captured by the receiver module after a certain period of time. Further, the autofocus calculator multiplies this time to a known wave propagation rate and divides the result by two, obtaining the exact distance value. By sending the emitter to the desired area, the user gets optimal focus, orienting the attention of the viewer precisely on this site of photography.

The second (passive) mode is somewhat different. It uses special sensors (photodiodes), measuring the intensity of the glow and a special processor that determines the focus by the magnitude of this parameter. In practice, it looks like this: the sensors fix the intensity of the glow, then the processor shifts the focus, after that the intensity repeated measurement occurs if the flux density increased, the focus is considered acceptable. If not, the focus displacement occurs. And so before the maximum intensity is detected. In matrices of serious cameras, up to 40-60 photodiodes are present.

Based on these principles, the most famous focus systems are working: phase, laser, contrasting and dual-pixel. And then in the text we each option, assessing their basic advantages and disadvantages.

Advantages and disadvantages of laser autofocus

In this case, a laser emitter and receiver are embedded in the phone camera model. The first generates a narrow-controlled beam, the second receives the reflected signal. As a result, the focus pointing speed is reduced to thousandth fractions of a second. Usually it is about 250-300 milliseconds, since the laser spreads at the speed of light.

The main advantage of the laser focus is a high speed of the module reaction, and the main drawback is frequent failures. A narrow laser emitter sometimes "shoots" by the target, and the reflected signal is easily lost, especially on open spaces. Therefore, the laser autofocus in the smartphone chamber in most cases works in a pair with a phase or contrasting version of the guidance.

Phase focus features

The technology is based on the crushing of the beam passing through the lens into two streams. This is done in order to measure the distance between the flows passing through the opposite edges of the lens. If this distance is placed in certain values \u200b\u200bspecified in the data array, the picture is considered focused. To fix the distance, special sensors react to light are used. Their signals are processed by the processor, which compares the read parameters with the base data array and gives the signal to move the focus to the desired side.

The main advantage of technology is the willingness to catch a moving object into focus. In addition, this option is faster than contrast autofocus. And this system can be used to count this parameter as the depth of field.

The main minus phase technology is a complex implementation. The system of prisms, mirrors, lenses requires ultralow physical alignment and at least scrupulous software configuration. In addition, the accuracy of such a focus depends on the lens torque, and the mobile phones with this parameter have big problems.

Pros and cons of contrasting focus

The technology does not change or the matrix nor the optical system of the smartphone camera. As a sensor, either the entire photo seensor is used here or part of it. The processor reads the current histogram from the sensor and evaluates the frame contrast. And then the lens is given a command to shift the focus, after which there is a new reading of the histogram with the revaluation of contrast. And the whole cycle is repeated until the maximum level of contrast in the selected frame area, which is focusing.

The main advantage of technology is a combination of simplicity of implementation, cheapness of design and compact sizes. Such autofocots use all manufacturers of budgetary smartphones.

The key disadvantage of this option is a very slow speed. Sometimes the processor goes into the perpetual "focus hunt" mode, which ends the loss of a rare frame.

Dual Pixel Technology

This focus technology is used in expensive mirror chambers. In mobile devices, it is still used only in Samsung flagship models, intentionally understating the resolution of the photographic matrix with a simultaneous increase in its physical dimensions.

These triggers are coming because of the desire to tie an individual sensor that responds to the intensity of the luminescence to each pixel of the photographic sensor. Then the signals from the sensors are processed by phase and along the contrasting algorithm of focusing, seeking not only perfectly sharp, but also the most contrast image.

If, in the case of a classic phase focus, the proportion of sensors accounts for no more than 10% of the total number of pixels in the chamber, then in the case of Dual Pixel, they are divided into 50/50. Simply put, each pixel is a photosensitive element and a sensor at the same time. This technology provides more accurate and fast focus.

From the disadvantages of Dual Pixel, it should be noted a very difficult implementation of such solutions. Only flagship devices are equipped with focuss, for example, devices from Samsung S-series (from the seventh model and above). There is something similar in the latest iPhone (from the sixth model and higher), but Apple has this focus technology called Focus Pixels, and it is closer to the usual phase autofocus than to Dual Pixel.

Automatic focus is a mandatory part of the chamber of most modern mobile. This function is necessary, since it is often the only way sharpness of the snapshot to obtain the framework of the required quality. And if in full-fledged cameras, it is often possible to configure the focusing manually, most of the mobile phones do not have such an opportunity, and therefore it will not work in the picture the picture in other ways.

Using autofocus

In mobile phones and the automatic focus function is activated by default and is used when conducting any picture. To make focusing, it is enough to click on the function key of the machine for the picture of the snapshot. Also, many fix the current frame when pressed to the appropriate touchscreen. The device will automatically determine the object relative to which it is necessary to adjust the focus, and makes the desired shot.

Modern mobile phones also support a more complete automatic focus mode, which is implemented using the camera shutter button. For the configuration, the user needs to pull the key to approximately half. This allows the camera to focus, setting sharpness and brightness.

After the autofocus is triggered and obtaining the corresponding signal, the user can choose a button to work the shutter. Similarly, the focus button on the touch screens is running - the user must press and hold the key until the camera configures the focus. After releasing the finger, the user will make a snapshot that will be saved in the device's memory.

disadvantages

Nevertheless, there are some disadvantages in autofocus technology. Often, automatic focus cannot determine the object relative to which it is necessary to perform sharpness settings. Sometimes the camera is not able to find several objects for focusing, which also lowers the picture quality.

Nevertheless, with the release of each new mobile device, the automatic focus technology is improved and its functioning improves, which allows you to make good and high-quality frames. Also, some modern devices are equipped with setting manual focus parameters, which will solve these problems in the work of some pictures.

In all digital cameras, whether it is a cheap soap, or expensive mirror, there is an automatic focus. Why then do you need manual if the system itself copes well? A logical question, and the answer to it is also logical: often automatic focusing works incorrectly, sometimes very slow and inaccurate. Therefore, knowledge of the work of focusing and its configuration is greatly expanding the creative abilities of any photographer and who would have thought, ensure the right focusing in different situations.

Manual focus allows you to highlight the main object in the frame or, on the contrary, to draw the viewer's attention to the details of the picture. Today, we will talk about this - about focus and situations, when it is more appropriate to apply a manual focus.

Focus points

Focus is a certain point where the rays reflected from the image converge. Therefore, that the image was "in focus", the focus point must be on the matrix of the camera. Focus guidance allows you to put priorities in the image, causing the attention of the viewer to the main objects, and not unimportant items.

The focus point is a point in space, and it is in it that the subject is placed. The image of this object turns out to be clear on the matrix. The choice of the point is determined by the photographer's solution to choose the most important item in the frame and send all the attention of the viewer.

In expensive mirror chambers (even in firecrackers), the user is offered a choice between specific focus points. It is also possible to choose everything at once. If you choose the focus on one point, then the picture will be sharp only on the site of the image that the selected point in the viewfinder coincides. If you choose the focus on all points at once, the automation itself will select the focus in accordance with your own intelligent algorithms. Often, automation flies and spoils a snapshot.

In accordance with the class of the camera, the focus points may be much or not. Inexpensive initial leveling mirrors are equipped with 11-point focus systems. Excellent example - photo gun Canon EOS 700D.

Dear professional cameras have 61 focus points. Example - camera Canon EOS-1D X.

Sales autofocus

Do not think that such a phenomenon is rare. Even in expensive mirrors, autofocus slippers are not excluded. This is due to the fact that the focus is selected automatically, and often the camera tritely "does not know" the goals of the photographer and, therefore, focusing not on the object that the photographer has conceived. Sometimes the system cannot determine the specific focus point, and then the focus buzzes, trying to "aim" on an unknown target. The intelligent focusing algorithms used are often guided by incorrect objects in the far or middle plan.

Nevertheless, automatic focus is important. It is not possible to manually manually target objects and dig in the settings, especially if the events in the frame happen quickly and do not allow to wait. Therefore, in the reportage shooting, automatic focusing on all points is always useful.

I wonder: in compact inexpensive soapboxes, the problem with focusing is practically absent. "Soapits" usually focus on infinity, with the result that each object is in focus - and the object in the foreground, and the horizon, and the average plan. However, it strongly limits the creative potential of the camera and the photographer itself - it is impossible to allocate a specific object and send all attention to it. Therefore, to a greater extent, this is a flaw, and not an advantage.

Applying focusing newcomers

Professional photographers when communicating with newbies, recommend instead of autofocus on all points to use only one central focus point. The newcomer is much simpler through the optical viewfinder of the model to determine the center of the frame at the time of shooting.

In this case, the technique of receiving the snapshot will be such: first choose the main object of the shooting - it should turn out sharp in the frame. Then in the viewfinder place it in the very center of the frame, combining with a focus point (which is in the center). Next, clamp the descent button half to lock autofocus. Most cameras make up a characteristic squeak. Then the descent button is clamped to the end.

The result is a photo with a sharp object right in the center of the frame, the remaining details outside the focus, less sharp. Attention to them is riveted weakly. In the art plan, such pictures look very good. In this case, it was about using the central focus point, but it could easily be the right or left point. Then the main object of the shooting would have to put on the right or left side of the frame to be in focus.

Automatic focus modes

Each company that is engaged in the production of photographic equipment uses its own intelligent focus algorithms. The result they give approximately the same. The modes under which these algorithms are used may be called differently. For example, in camerasCanon has a modeOne.Shot. - It is intended for photographing stationary and fixed objects. For objects in motion Canon has provided modeAlSERVO. - Some other algorithms for determining the main objects and the guidance of sharpness will already be used here.

W.Nikon These modes are called otherwise:SingleSERVO - for fixed stationary objects,Continuous.SERVO - for moving. Also, both brands have predicative focus modes when the system tries to predict the further movement of the object in order to ensure the correct focus.

However, despite the development of technology and improving algorithms, often autofocus waves. Here are examples of photos with focus errors:

Quite often, photographers have to deal with the promotion of autofocus, and the reasons here are often some: the shooting conditions that are "deceiving" the focus system.

When appropriate to use manual focus?

The very first and banal moment, when it is best to manually focus on the object, it is weak lighting. Often, with a weak lighting, the camera lens begins to rotate there and cannot specifically determine the correct object. However, this problem is partly solved due to the highlighting of autofocus (the front plan is highlighted, which makes it possible to provide the right focus), although not to the end.

Macro shot is another mode in the chamber, when it is better to manually shut the sharpness of the object. The problem is that when macro photography, work goes to very narrow bands, respectively, any inaccuracy will spoil the snapshot.

Portrait shot. Usually there are no problems here, because in this mode the system focuses on the eyes of the model. However, professional photographers sometimes use manual focus to highlight lip lines or another part of the face. However, this is a completely different story.

Most often I hear from most photographers of any level of complaints of this kind: "My images are not sharp" and "I can't catch a focus." Many accuse their equipment and, indeed, there are many cases in which the equipment is guilty. However, I found that the overwhelming majority of cases are simple user errors. They are often reduced to a lack of understanding how the autofocus system works (AF). This article will give you a better idea of \u200b\u200bfocus and sharpness, and hopefully will help get photos that you will be happy!

1. Customize your diopters

You ask, mine what? Your diopters - or your eyepieces. You will never know whether the camera is well focused on the object, if you yourself can not see what is in sharpness through the eyepiece of the viewfinder. Side of the eyepiece (as shown below) there is a small wheel to adjust the focus of the eyepiece according to your vision.

You can configure the eyepiece on a fairly large correction, but if you need even more correction, then for DSLR / SLR cameras of many largest producers, replaceable diopters are available in the range from -5 to +4. No, it will not help your autofocus work better, but it will help you understand when it misses and adjust the situation with manual focus.

2. Observe your viewfinder

What damn all these things inside? At this place, you may have to get instructions (remember that paper book that was with your camera?). Most of the usual DSLR cameras have 9-11 focus points. The best of the best, professional cameras can have from 45 to 51 points (although on the fact you can only select 11-19, the remaining points are optional).

There are two types of focus points: located in the same plane and intersection points. The points of one plane work only on the contrast lines, directly perpendicular (at an angle of 90 °) to their orientation. So, if you look through your viewfinder, similar to the above, you see that most of the points are rectangles, some are horizontally oriented, some - vertically.

The points of one plane will only work perpendicular to their orientation. So - let's say you removed the tree - the vertically-oriented point of focus could not find the edge of the tree trunk, and the horizontal could be. You can use it for yourself when choosing a focus point, which will be fixed on the line you need, and ignores those on which you do not need to focus.

The intersection points (eng. Cross Point Focus Points) will work with contrast lines located in any way. Most chambers have one focusing point of intersection in the center, surrounded by points of one plane. The newest cameras today contain intersection points at all points of focus.

Each focus point also has a certain sensitivity. For most, a lens is required with a limit diaphragm value of at least F5.6 to at least use autofocus. On most cameras, the surrounding points of autofocus is precisely such sensitivity, and the central point provides increased sensitivity if you use a lens with a limit diaphragm value of at least F2.8.

So if you work in low lighting conditions, you can achieve better autofocus using a central focus point. If you do not even use a lens with a diaphragm F2.8 or, even better, there are no limit of light that contribute to the premitious use of the central point, it still can give a more accurate result, since it is an intersection point.

When we look at the rectangles of focusing points, it is worth remembering that the real area of \u200b\u200bthe sensor is 2-3 times greater than what is displayed. Keep it in the head when focusing. If you fix the focus on someone's nose, remember that the person's eyes will also fall into the valid sensor zone. Autofocus is rather fixed on the eye than on the nose, because the eye has more contrast around the edges than flat lighting on the nose. Often it may not matter, but if you work on a very small depth of field, you will feel the difference in which the image area will be the sharpest.

3. Thug hands help your lens

Most autofocus systems have a certain amount of errors or deviations and can actually miss the optimal focus point due to mechanics and inertia of the lenses. You can minimize this influence by manual focusing of the lens close approaching the necessary focus, and then allow the autofocus system to complete the tip. Or, if it seems to you too difficult, at least letivate the autofocus to make two attempts for the correct guidance. Hold down the descent button to set up an exemplary focus, and then press again to make exactly it.

The advantage of a higher level lenses is that they allow full manual control, even when autofocus is fixed. Cheaper lenses do not allow to edit the focus manually after fixing, although this is a good way to make sure that the focus is perfect as much as it can be.

4. Find a good line

Autofocus systems work on contrast lines, so they may experience difficulties on non-contrast facilities (for example, on the cheek or forehead, on a white dress or black tuxedo, sand, monochrome walls, etc.). On areas similar to this, autofocus can be guided all day, and never and not fix. The approach is to find the "best line" - it can be eyes, lines between contrasting shirt and costume, between sky and earth, door passage. All that is contrasting will help autofocus work better and faster.

Zone of weak focus

The best area for focusing

5. Do not use the focus mode for all points.

Unless you are in a terribly rapidly changing situation that requires an incredibly operational tip, it is better to avoid focusing mode for all points. This mode does not know what you want to focus, and is usually fixed on what is closer to the camera. There are situations in which it is necessary, but they are few and rare.

6. Focus and change the composition - but do it correctly

I used to focus and change the composition, all the time using the central focus point. I fix focus and then anew component frame. I somehow read a few articles who claimed that you should not do this - that you should use a point close to the area where you want to focus. Theoretically, this is justified by the fact that during the transfer of the camera due to the movement of lenses and shifts the value of the angle, the distance between the subject of the shooting and the lens is also changing.

If you use the focusing point immediately induced to the object and do not reconnect the frame, it will not be a change in the distance between the object and the lens, and therefore the erroneous focus. So, I decided to take a few pictures to show you that it is so - and it is not.

There was absolutely no advantage in using the nearest non-central point without changing the composition. In fact, focusing using the center point and the reconnect was indeed more accurate in all cases, except for one - macro. I made frames at all focal lengths from 17mm to 200mm and checked all distances from macro 10 meters - with the same results.

Each test using the central focus point and the reconnect of the frame led to a sharper picture. Large sharpness from the use of the center point and reconnect, less - from using an external focus point directly on the object. To clarify - the above theory is true, in the fact that you lose the sharpness, shifting the frame from the fixed center point. What is not true - this is what the use of an external point right on the object will return sharpness - will not return.

I think there is a high probability that it is on my camera that the central point of focusing is three times more sensitive than any of eight other points, and it is most accurate. But the same is the case with many cameras, with the exception of high-tech new models like Canon 1DS Mark III or Nikon D3X. Other possible The reason is that most lenses are the most cutting in the center and lose clarity to the edges.

Here are the three most typical examples of what I took off on two different cameras. Insert is an inscription on a scale of 100%.

The central point of focus, without changing the composition. Lens 50mmf. 1.8.

Lens 50mmf. 1.8. Central focusing point. The camera is translated left after focus fixing.

Lens 50mm F 1.8. Left focusing point. Focus on the object.

What can I say - switch the focus point or not, in my opinion, the question of time. But try yourself, your result may differ.

A small note on the macro - such frames should always be removed with the tripod and manual tip to sharpness, due to the extremely small depth of the sharpness and proximity of the lens to the shooting object.

7. Use the correct focus mode

Most of the DSLR cameras have at least two similar focus mode. The first is "One Shot" (Canon) or "Single Servo" (Nikon). In this mode, it is assumed that the station object. The focus is fixed, you get confirmation of the illumination on the inner display, and then descend the shutter. You will not be able to lower the shutter if the focus was not fixed.

The second type is "AI SERVO" (Canon) and "Continuous Servo" (Nikon). This mode is designed to shoot objects in motion, including sporting events, wildlife, etc. The camera finds an object using the focus point, and the focus will change constantly to keep up to follow the object, but never fixes. The descent button will work, even if the focus is not performed.

Some cameras also have other modes, such as "AI Focus" on Canon, which are good if the object is static, but may begin to move, as in the case of small children. Autofocus will fix on the object, but if the object is moving, the camera will switch to AI SERVO mode to track it.

The third opportunity is a preliminary focus - created for objects that move towards you or from you. The camera will try to predict movement and provide you with an acceptable focus.

8. Do not change the depth of field for good focus

Although the use of greater depth of sharpness with a smaller aperture can increase the "visible" image sharpness, remember one thing: it doesn't matter what the depth of field, the focus point is only one. So always train in the technique of good focus, regardless of the depth of field used.

9. Use a tripod or find a support.

When we make a photo, we are all unconsciously swinging back and forth - in particular, we lean to the object with a heavy set of chamber and lens. It `s naturally. All this is manifested in one degree or another. And if you take off with a very small depth of field, this is a short distance that you move can seriously affect the sharpness and desired clarity of focusing. If you use the depth of sharpness of 4 inches, the deviation to 2 may have a catastrophic effect. So, use a tripod.

Now I have to add, because I myself use a tripod - i hate them. They affect how I work and most of the time for shooting. Thus, if you prefer to avoid using a tripod, at least, spend time on working out the position of a good photographer. One leg before the other, the legs are a bit bent, the hands are pressed against the sides, do not hang out in space (remote controls can be useful), and the body weight is distributed in the center over the legs.

10. If still unsuccessfully - use manual focus

Every time I hear a deep breath when I propose this to photographers. They regularly argue: "I remove only in manual mode, never on the machine." But invite them again manual focusAnd they will look at you as if you just offered them to sell our children. Manual focus in most cases (considering that your diopters are configured correctly) will help achieve the best and most accurate result. Especially in this digital age, when so easy to see the image with an increase of 100% or even 200% on our monitors.

In fact, if you browse informal autofocus specifications, you will notice that they are not too accurate. Here is the specification for "sharpness": The image is considered sharp if it seems sharp on the fingerprint 6x.9 from a distance of 10 inches. Yeah, like that. No 100% "zooms", no prints 20x30. Just this.

Today a number of new cameras are made with the built-in "Live View" mode. This can be a useful tool when manual focus. Turn on your "Live View", bring the object / focus point and check the sharpness on the display. It does not particularly work well in my case, since I almost always be in the conditions of bright lighting: deserts, beaches, etc. - But for some it will work perfectly.

One remark about the image from above. I usually use it to show the switching lever on the manual focus, but the other switch is also of interest: "From 1.2m to infinity" and "from 3m to infinity." This switch refers to what I said earlier: do not force your lens to hunt behind the focus through the entire possible space. If you know that you will not focus on any closer than three meters, move the lever to the appropriate position, and the lens will not be forced to wander in search of the focus. This can lead to more accurate primary automatic focusing.

11. What should I focus on?

For portraits, a close-up opinion, in general, developed: Eyes. For other types of portraits, this is still a face, unless you want to focus on any other part of the body intentionally. Clean the exact focus where you want to send the viewer's view.

In the landscapes, everything is not always so simple, but you still have to adhere to the rule mentioned above. Do not bet on the fact that "this is a landscape with a wide viewing angle, focus on infinity." If you have an object in the foreground, focus on it and allow your depth of sharpness to transfer the image to the background. If the foreground object does not have a sharp focus, it confuses, since we usually see more dramatically close objects, and not distant.

Now I can work with focusing on the "hyperfocal distance" ("Hyper Focal Distance"), but it is beyond this lesson. If you are interested in this topic, which is likely to use a quick search in Google.

12. Object in focus, but does he sharpen?

Focus and sharpness are two different things. An explanation of the concept of sharpness can take another individual lesson, so I will only notice a few useful moments.

If an image outside the focus, you cannot return it to the focus by adding sharpness. You just get a very sharp unfocused picture. Most of the raw images need to add sharpness of any kind. Do you use "Smart Sharpen", un-Sharp Mask or upper frequency filtering techniques, most of the raw images won from sharpness. Nevertheless, while I gradually started using cameras of more than high quality, I began to see less and less need in adding sharpness, and now I use this tool about only 25% of my frames.

Remember also that sharpness depends on the final product. You will not equally enhance sharpness in the image that will go on the Internet, and for the 25x20 imprint. And, holding it in the head, if you intend to sell your photo through the stock agency, it is not necessary to add sharpness at all. Most will tell you what it is not necessary to do this, because you cannot predict what the image will be used and in what size.

On the left are the images directly from the camera, rectified (eng. "Straight out of the Camera"), right - with added sharpness.

13. Consider excerpt

Exposure is another parameter that can lead to a lack of sharpness. Each person has a limit of exposure value on which it can take from hand at lenses with different focal lengths. Some people are more stable than others, but if you are shooting on an exposure that is not able to compensate for the movement (trembling) of your hands, your image will be blurred. If we talk about standard and wide-angle lenses, most people can consistently shoot on them from about 1/30-1 / 60 share of a second.

Larger telephoto lenses require much shorter exposure. The general rule from which people start are: "1 to the focal distance of the lens." So, if you have a 200 mm lens, remove for 1/200 a second of a second, and repel from this level to understand your further opportunities. Personally, I am shaking as California on the worst days, so I usually remove on shorter excerpts. It also depends on how far you are from the subject of shooting, as what you are further, the more noticeably movement.

If the object is moving, holding the camera in stability or on the tripod will not help - you still need to choose a satisfactory shutter speed in order to stop the action. Most begins with 1/250, but it depends on the speed of moving the object. Requirements also vary depending on whether you are shooting in a static position or follow the object. If the second, you can choose a longer shutter speed and also get some interesting effects. This will allow you to show move on the background, but will fix the object itself.

Image stabilization systems on lenses allow you to remove from hand to shorter excerpts (up to 3 steps), but will not "stop" the movement is better than the lens without a stabilization system. You can fix the action only with shutter speed (or high-speed flash).

Picture not Outside focus. Exposure is too long.

14. Choose the correct exposure

Correct exposure and good lighting (essence of the whole photo) - the key to good focus and sharpness. While the sharpness is determined by the contrast line, if you undepleted the frame or removed in the dim lighting, the image will not be sharp, even if all other parameters of good focus are observed.

15. I did it all. I'm still out of focus!

There is a small probability that something is not true with your equipment. The lenses from third-party companies are sometimes not very successfully designed, and therefore they will not always function perfectly with brand chambers. Some work perfectly, others - no. But sometimes even branded lenses are not perfect.

Cameras such as Canon 50D and 1D / DS Mark III are excellent fittings for more than 20 different lenses, so if you know that one of the lenses exactly exactly all the time focuses in front of your object, you can adjust the chamber To fix it. If such an opportunity is not available, you need to determine whether your lens, or and lens, and the camera do not need.

Here is the test you can spend at home to understand the case in you or in the chamber. Find a ruler and post on the table away from the camera. Put the camera to the tripod and open the aperture as much as possible. Take a picture at an angle of 45 degrees, focusing on a specific label - in this example, on the six.

If this is the label that you will see the most clearly, opening the image, then with your equipment everything is in order - come back to work on the technique! If the sharpest point in front of this label or for it, then you will learn that this is the problem of equipment, and it should be attributed to the service.

16. Conclusion

I looked at a lot of questions in this lesson - it's great that you read to the end! It seems to me that a good focus and sharpness are two of the most important technical parameters that need to be saved in the image. It can create a difference between those frames that they look at professionally and those that look like the work of an amateur (and we all want to look like professionals - we are such or not).

Please feel free to leave your opinion in the comments - did you ever have problems with focus and sharpness?

One of the essential problems in many beginners, and quite experienced photographers - achieving the desired sharpness of the obtained images. "Get into sharpness" - it sounds very simple, but in practice this action may be a bit more complicated.

On the one hand, there are many ways to get a photo in focus. What method is best to choose and how to use it to achieve the desired results? Let's look at some of the most common and efficient ways to focus the camera.

Frame autofocus

One of the easiest ways to focus the camera is to use frame autofocus, which in most cases is the default setting and one of the most effective ways to photograph.

In migrant mode, you simply targe the camera to the object and press the shutter button halfway.

It blocks the focus on the object, allowing you to reproduce the image without loss of focus if necessary. This method is called focus and recomposition.

For example, in the image above, if you want the bridge to be in focus, you need to position the central point of autofocus on the bridge and click the shutter button halfway.

Then you comply with a snapshot, as you can see above, and press the shutter button already to the end to take a photo. As a result, you will get an object in focus, even if you reconciled the photo.

This option is good for landscape photos or shooting of fixed objects.

Continuous autofocus

Obviously, there are no perfectly fixed objects, so you need a focusing tool that would allow tracking moving objects, while maintaining them in focus.

In this case, continuous autofocus can help. All you need to do is capture an object using the viewfinder, click the shutter button halfway and trace the object when it moves, while at the same time keeps the shutter button halfway. Thus will continuously adjust the focus (hence and name).

Most entry-level cameras require that you use a central point for continuous autofocus, but if your high-level camera, you can determine which autofocus point is used to track the moving object.

Naturally, this type of focus is best suited for shooting, for example, wildlife or in which you need to quickly configure focus.

Autofocus with face recognition

Not all cameras have autofocus with face recognition, but if it is still available, it is a valuable tool for portrait shooting. It uses algorithms for recognizing figures resembling human faces.

In Live View mode, the focus on the face is visible in the process of work in the form of a frame around the face.

All you need to do is press the shutter button halfway to specify the area on which the focus is needed and then take a picture.

Focus point selection

Regardless of which autofocus mode you use, you must have an active point of autofocus on your object. Otherwise, the object will not be sharp.

As a rule, there are two ways to select an active autofocus point: Select or automatically automatically using the camera. Now most cameras are quite well choosing a suitable point of autofocus in most situations. But still not always perfect.

In situations where time does not matter, for example, in portrait or landscape shooting - try to select the autofocus point. Watch the "User Guide" of your camera, if you do not know how to do it.

However, it should be considered the fact that your lens will be best focused when using the central autofocus point. If you use another point to get the focus, the image may not be sharp enough.

Focusing rear button

Another way to get an image in focus is to use the focusing rear button. Depending on the specific camera, you can have an autofocus button on the rear case panel by clicking on which to the end, you will focus on the object.

This is beneficial for a number of reasons, including because it prevents accidental pressing the shutter button and, therefore, shooting photos before you (or the camera) were ready for this. When shooting moving or multiple objects, focusing rear button also allows you to focus on your main object. In other words, the release of the autofocus button, you do not allow the camera to make a focus on a new object, and you can still take photos with a focus on the main object.

Manual focus

The process of manual focus may differ slightly depending on the specific chamber or lens, but the following steps are in principle standard:

find the AF-MF switch on the lens and move it to the MF position
rotate the focus ring on the lens until you see that the desired object is
using the Live View mode, increase the object zoom to check its sharpness. If necessary, adjust with the focus ring.

That's all!

Manual focus can take a little longer than automatic, but it works better in a variety of situations, for example, in macro shot, when you shoot through something (say, using a plant in the foreground to turn the object in the background), objects In places with a pile of people (street scenes), as well as in low light situations. In other words, in situations where automatic focus "resists", do not be afraid to switch to manual.

Hyperfocal Distance

A more complex and technical method for producing focus is to calculate the hyperfocal distance. In principle, it lies in the fact that you must use the calculations of the depth of field for the lens that you use to find the nearest point in the picture where you can still get an acceptable sharpness.

Finding this point will focus on the place that will give the best depth of field and maximizes the area of \u200b\u200bfield into photography.

There are several ways to determine the hyperfocal distance, but the most simple among them are the following:

focus on one third of the bottom of the frame. Since the depth of the sharpness extends about two times higher than the focal point, focusing on this third will help you maximize the depth of field;
you can use the application for smartphones, such as HyperFocal Pro for Android (shown above) or Digital DOF for iOS devices that will get rid of you from the need to make any mathematical calculations.

If you are a landscape photographer, the use of the hyperfocal distance will be especially useful for you.

Focal Focus Stacking

The final method, which we consider in this article, getting the perfect focus on photos is the use of the Focus stacking method, which is achieved upon subsequent processing.

In fact, you take several different photos, each with its point focusing (that is, with a focus in the foreground, middle and rear) and combine them together in one image upon subsequent processing. The resulting team photo will be sharp from the foreground to the rear.

This method is especially useful for macro shot and shooting still life, as well as good to use for landscape photography.

Caution As for the Focus Stacking method: There can be no movement in the picture.

This is explained by the fact that you are removing several exposures at different times, so if something in the frame is in motion (for example, a tree from behind the wind), it will cause halyols. Everything that moves in the photo will be blurred.

Another difficulty using this method is that you need to configure the focus for each snapshot, without disturbing the position of the camera. Otherwise, the cadres used will not be perfectly combined in post-processing.

So, now you have a number of methods that will help to configure the focus on the objects removable. For their development it will take time. However, this is exactly worth it. Act!

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