Focusing skills in sports photography

In sports photography, focusing is a difficult skill to master, because the subject of sports photography is very dynamic and fast, and it is unlikely that you will slowly ponder and focus on perfection. Professional sports photographers always follow the focus: they constantly change the focus, so that competitors can keep clear images in the picture at any time. However, it is difficult for a beginner to practice this technique perfectly.

An easier way is to use the autofocus system on the camera. Although the autofocus system can focus quickly, it can't play its due role if it is used improperly. That is to say, only when the subject is properly left in the ranging frame in the center of the viewfinder can the purpose of accurate focusing be achieved. If the camera is equipped with a lens with a short focal length and a large viewing angle, it is easy to arrange the moving subject in the ranging frame in the center of the viewing frame; If the camera is equipped with a long focal length lens of more than 200 mm, it may be difficult to track the subject and aim at the ranging frame because of the small viewing angle. In order to adapt to this situation, we might as well change the above habits, and we can use the ranging frame to track the subject temporarily without considering the scope of the viewing frame, which may make us feel more relaxed. If you want to shoot the athletes outside the center of the picture, and you also use the automatic ranging system, you must use the focus automatic locking device to fix the focus. If the subject moves violently, it is not allowed to use the locking device in time, and the composition requires the subject to be outside the center of the picture, then the automatic focus must be cancelled and replaced by manual focus.

There is also a commonly used focusing method when shooting moving photos, which is trap focusing, that is, when the subject enters the predetermined focus, the shutter of the camera is pressed immediately. Some advanced cameras have this performance. Trap focusing is very suitable for sports photography, and this method is the most ideal for shooting the action of high jumpers jumping over the beam. When shooting, you can first focus on a point where the athlete may cross the crossbar, and then lock the focus so that it does not move back and forth. Finally, press the shutter according to the situation when the athletes fly over the beam, and you can take high-definition photos.

It is worth mentioning that if the subject is moving at an extremely fast speed, such as a racing car, we must also press the shutter in advance when using trap focusing technology. In other words, the shutter should be pressed just before the subject reaches this position. Pressing the shutter in advance can make up for the time difference between pressing the shutter and actually opening the shutter. Of course, at present, the focusing ability of some advanced autofocus cameras has caught up with the speed of racing cars, and even if the racing cars gallop across the screen at the highest speed, they can be photographed. If you don't know what animals will pass before shooting, but only know that they will pass through a certain area, then you can use the area focusing method, try to use high-sensitivity film when shooting, and try to use a small aperture according to the light conditions and film sensitivity.

When focusing, make this area within the depth of field according to the Jing Shenbiao on the lens, and set the accurate focus at 1/3 near this area of the camera, because the depth of the foreground is less than that of the backcourt. By doing so, we can get better results. If athletes appear in the distance, they can be filmed in the way of hyperfocal distance. From the Jing Shenbiao on the lens, you can find out the range of depth of field corresponding to the aperture used in shooting, and then turn the focus ring so that the back depth of field mark is aligned with the infinity mark of the focus ring, so that you can get the maximum depth of field under the aperture used. If the athletes who want to take photos will appear in several different areas regularly, you can make a circle with paper tape and put it on the distance ring, preferably white paper with several special regional signs on it. Just focus on the mark before taking a picture, and you can determine the focus position very quickly without focusing through the viewfinder at all.

The purpose of focusing is naturally to obtain high-quality images, and clear focusing is the requirement of the tomb. But for beginners, it is difficult to get a clear focus in every photo, because there are many factors that affect the focus. If you don't grasp it well, it is difficult to get a clear image. Here are some good ways to keep the focus clear for beginners' reference:

1. Prevent vibration

Vibration will make the image in the photo shake and blur, even if the original focus is very accurate, it will also affect the clarity of the image. Vibration usually has two reasons:

First, the camera shakes, that is, when the shutter is pressed, the camera shakes due to unstable grip.

The second is the motion of the subject, that is, at the moment when the lens shutter is opened, the subject is in motion, and the shutter speed is not high enough to freeze the motion, so the image is blurred.

To avoid camera vibration, measures can be taken from three aspects: ① Install the camera on a tripod and stabilize the camera. If the tripod cannot be supported due to shooting conditions, a monopod can also be used. ② Increasing the shutter speed (usually 1/250 seconds shutter speed) can reduce the image jitter caused by camera vibration. (3) adopt the correct method of holding the machine. Without a tripod, the correct posture of the camera will directly affect the stability of the camera. There is only one way to overcome the dynamic blur of the subject, and that is to increase the shutter speed. As long as conditions permit, the faster the shutter speed, the better the effect.

2. Don't pursue small aperture unilaterally.

Beginners think that a small aperture will increase the depth of field and will definitely make the image clear. Therefore, they often turn off the aperture very small regardless of the occasion, especially when they are not sure about focusing. They believe that a small aperture can help them. However, the final result is often not ideal, because using a small aperture will lead to a decrease in shutter speed, which will cause camera vibration. Therefore, it is not the best policy to pursue a small aperture unilaterally. The correct approach should be to actively use high-speed shutters and tripods.

A famous photographer has his own unique focusing method. Every time he shoots, he carries three cameras on his back. The focal length of each camera is determined as follows: from his position 10 m, zoom lens 100 mm and focal length100; 20 meters away, with a 200 mm zoom lens and a focal length of 200; 30 meters away, with a 300 mm zoom lens and a focal length of 300. He believes that there is no need to be distracted to adjust the focal length when shooting, and you can judge which camera to use according to the visual results.