Ask the master to introduce the knowledge about wide-angle lens.

A wide-angle lens usually refers to a lens with a focal length of about 17 to 35 mm The basic characteristics of a wide-angle lens are its wide viewing angle and wide field of vision. The range of scenery observed from a certain viewpoint is much larger than that seen by human eyes at the same viewpoint; The depth of field is long, which can show a fairly clear range; It can emphasize the perspective effect of the picture, be good at exaggerating the foreground and express the sense of distance of the scene, which is conducive to enhancing the appeal of the picture.

Wide viewing angle, covering a wide range of scenery. The so-called wide viewing angle range means that at the same viewing point (the distance from the subject is constant), the scene is viewed with wide-angle, standard and telephoto lenses with three different focal lengths. As a result, the former shoots more up, down, left and right scenes than the latter. When the photographer has no retreat, it is difficult to take a complete picture (such as taking a group photo) with a standard lens of 50 mm ), using a wide-angle lens can easily solve the problem. Furthermore, for example, shooting a vast Yuan Ye or a tall building in a city, perhaps only a part of the scenery can be photographed with a standard lens, which cannot show the breadth or height of the scenery. Shooting with a wide-angle lens can effectively show the open momentum of large scenes or majestic buildings.

Short focal length and long depth of field. Photographers usually rely on the short focal length and long depth of field of wide-angle lenses to bring the whole scene from near to far into a clear range of expression when shooting a wide scene. In addition, when shooting with a wide-angle lens, if a smaller aperture is used at the same time, the depth of field of the scene will become longer. For example, if a photographer shoots with a 28 mm wide-angle lens, the focus is on a subject about 3 meters, and the aperture is adjusted to F8, then from 1 meter to infinity, it almost enters the depth of field. It is precisely because of this long depth of field that wide-angle lenses are often used by photographers as fast-moving lenses with strong maneuverability. On some occasions, the photographer can quickly capture the picture by manipulating the wide-angle lens without focusing on the subject.

You can emphasize the prospect and highlight the contrast between far and near. This is another important performance of wide-angle lens. The so-called emphasis on foreground and far-near contrast means that wide-angle lens can emphasize far-near contrast more than other lenses. In other words, the photos taken with wide-angle lens are closer and farther, which makes people feel that the distance has been widened and has a strong perspective effect in the depth direction. Especially when shooting with a super wide-angle lens with short focal length, the effect of being near big and far small is particularly remarkable.

Can be exaggerated and deformed. Generally speaking, it is taboo to use a wide-angle lens when the subject is exaggerated and deformed. In fact, it is not necessarily undesirable for the subject to exaggerate and deform appropriately. Experienced photographers often use wide-angle lenses to deform the subject moderately and take some unusual photos of very inconspicuous scenes that people ignore. Of course, using a wide-angle lens to express exaggeration and distortion should be based on the needs of the subject matter, and the second should be few and precise. No matter whether the theme is necessary or not, it is not worthwhile to abuse the exaggerated deformation of wide-angle lens and blindly pursue the bizarre effect in form.