Portrait photography Tips-Lens differences can change facial impressions

Understand changes in the face and background of focal length changes

The difference in lens focal length will change the mood of the photo. Where the difference of perspective is as follows. The size of the subjects in the photo has not changed, but the background range has changed a lot. As the focal length tends to the telephoto area, the angle of view becomes narrower, so the range of the background gradually narrows. In addition, the lens focal length is different, the shape of the subject will also change. When using a wide-angle lens, the shape of the face is distorted because of its near-large, far-small characteristics. Compared to a lens with longer focal length, the shooting distance is shorter when using the wide-angle lenses, so the nose and cheek parts that are closer to the lens are as prominent as the bulge. Conversely, when shooting with a telephoto lens with longer focal length, the distance between the faces is longer, and the distance difference between the parts of the face decreases with the length of the shooting distance, and the face imaging effect of the opposite angle lens is gradually presented. As mentioned above, when shooting the lens focal length is different, the impression of the characters will change a lot. What kind of focal length is used is the standard image, which varies greatly with the photographer's subjective preferences. such as the shooting, using a 35mm full-frame camera, the photographer himself relative like 50-70mm with slightly deformed photos. The appropriate deformation emphasizes the three-dimensional sense, highlighting the impression of the subject's face, which looks more refined and beautiful. However, it is not simple to say that the longer the better, because in the use of telephoto area when shooting, the overall face will give people a very flat feeling, and sometimes make people look fat. Therefore, you should carefully observe the characteristics of the subject's face and choose the most appropriate lens.

Understanding the relationship between focal length, shooting distance, and aperture
1, the longer the focal length, the closer the shooting distance, the brighter the aperture, the greater the effect of the blur

Understanding the theory of virtual production will make better portrait pictures. The background blur that is popular and frequently used in portrait photography is closely related to the focal length of the lens used, the brightness of the aperture (aperture value), and the distance between the camera and the subject. When the aperture value of the lens is constant, the longer the focal length, the more likely the background blur will occur. Of course, if the focal length is the same, the brighter the lens, the more likely it is to create a blur effect. In addition, the degree of bokeh will vary depending on the shooting distance. The shorter the shooting distance, the closer the shooting, the greater the effect of the blur. Therefore, if you want to get a large amount of bokeh, you should choose a lens with a shorter distance, a brighter aperture and a longer focal length. Just in the portrait photography, the first decision lens focal length, the composition is completed after the shooting distance is fixed, so in mastering the longer, more near, brighter the principle of this virtual, but also need to grasp the lens focal length and shooting distance relationship.

2. Grasp the focal length and shooting distance of portrait photography
Actual measurement of the shooting distance of a representative 5 kinds of composition

Shooting distance

※ 1: Less than the most recent shooting distance to use the lens when shooting.
※ 2: Shooting with 35mm full-frame camera. Brackets indicate the lens focal length required to shoot with the APS-C spec camera under the same conditions.

Use numerical values to grasp the relationship between focal length and shooting distance, and use it flexibly in the shooting scene.

The relationship between the size of the subject in the photograph and the shooting distance is shown in the table above. The longer the focal length, the longer the shooting distance is to keep the subject in the same size on the screen. If the person is 167 centimeters tall and wants to take a close-up of the chest, the distance from the 16mm lens is short enough to touch the character, while the 200mm lens must be over 3 meters. If you can remember this value to a certain extent, it is easy to grasp the lens of what focal length to use on the scene. Especially when shooting indoors, in most cases it is impossible to keep a certain distance from the model. If you want to take a full-body photo, it is almost impossible to use a lens above 200mm, unless it is such a wide place. By mastering the general relationship between the lens focal length and the shooting distance, you will not hesitate to select the lens.

3, observe the real picture
Grasp the different bokeh effects of focal length, shooting distance and aperture value (aperture brightness).
Lens focal length 16mm, change of blur effect when shooting distance 50 cm ※ shooting with a 35mm full-frame camera.

Even if it is considered difficult to produce the effect of the wide-angle lens, the aperture is large enough, the shooting distance is close, the subject and the background is far apart from the situation will also have a certain background blur effect. But at the maximum aperture, there is a certain depth of field. When the aperture is around F4, the background has become clearer. From the effect of the picture, to F5.6 can also feel a certain degree of bokeh effect, the smaller aperture shot image is similar to the pan-focus effect. If the background and the subject are closer, you can start to feel that the F4 aperture value will be even smaller, and it may be difficult to create a blur effect around the time of the film.

Lens focal length 35mm, change of blur effect when shooting distance 85 cm ※ Shooting with a 35mm full-frame camera.

After the focal length has changed to 35mm, the depth of field is still much smaller, although it is still a wide angle lens. The F2.8 effect at aperture is larger than 16mm, and the blur from the legend is similar to the blur effect between F4 and F5.6 when shooting with a 50mm lens. The viewing angle has changed compared to the 16mm lens, and the effect of the blur is similar to the 50mm lens, but the image is slightly different because of the difference in perspective.

Lens focal length 85mm, change of blur effect at 1.95 m distance ※ shooting with 35mm full-frame camera.

85mm already belongs to the field of the Cosco lens, its imaging and 50mm lens have the big difference. It is like having a dividing line that is invisible to the naked eye, which distinguishes the two. The depth of field is very small, F2.8 for eye focus, part of the front of the hair has been falsified, the arm also has a very obvious blur. When using a 50mm lens, the fluffy part of the neck and front of the hair is within the depth of field, and obviously the gap is larger.

Lens focal length 135mm, change of blur effect at 2.85 m distance ※ shooting with 35mm full-frame camera.

The blur effect is similar to the 85mm lens, but the viewing angle becomes narrower, so the impression of the photo is somewhat different. A longer shooting distance makes it easier to control focus than when using a 85mm lens. Although the shooting distance is not as long as the overall focus on the face is done, but the 85mm lens does not really focus on the control requirements are not so strict. The virtual size looks big, and the effect of the blur has a unique atmosphere of the telephoto lens. The separation between the photographer and the background is more explicit, which makes the whole picture of the subject be highlighted.

Lens focal length 200mm, change of blur effect at 4 m distance ※ shooting with 35mm full-frame camera.

200mm focal length In fact, the main dominant effect on the lens is the focal length, the aperture from F2.8 to F4, the effect of the blur and no other focal length of the lens when the obvious change. Even if the aperture is shrunk to F22, it is not possible to take a pan-focus photo of the whole Coke. The shooting distance is correspondingly longer, so not only the face, but also the whole body is in the same focal surface, even with F2.8 shooting, all parts are in a focal range. There is no difference in focal points between the parts of the face, whether it is the eyelashes or the nose, the focal surface is almost uniform.

The actual PAT test proves that the data is correct and the photographer needs to pay attention to the background distance and color.

The relationship between focal length, shooting distance, aperture value, and defocus can be calculated. However, it is also a complex problem to see that the shape and color of the background will actually make the impression of the whole picture. In addition, the distance between the subject and the background is also related to the blur. If you want to make the background larger, you should use a lens with a long focal length and a large aperture as much as possible, and you should carefully choose the tone and shape of the background. In order to enhance the atmosphere of the blur, you can try to add a highlight to the blur, which can make the whole picture look more crisp, more conducive to the use of virtual effect. From the point of view of controlling the focal point, using the aperture which is smaller than the maximum aperture shrinkage, you can get a larger depth of field, which is less prone to failure. However, the aperture value of the lens can have a great effect on the blur, so shooting with the aperture near the maximum aperture is the basic principle for a strong blur. The shorter the focal length of the lens, the more easily the blur is directly affected by the aperture value, which can be significantly different when using such a lens even if you shrink the first aperture. The use of telephoto lenses is mainly the use of long focal length to create a virtual effect. However, the lens used to shoot the 50-85mm focal length of a portrait is essentially the aperture value that dominates the blur effect.

The following small series for everyone to recommend a photographic professional more good study abroad institutions:
1. University of New Mexico
2. Cranbrook Art Institute
3. Commonwealth University of Virginia
4. Rochester Institute of Technology
5. University of California, Los Angeles
6. Yale University
7. Columbia University
8. California University of the Arts
9. Maryland College of Art
10. California College of the Arts
11. Art Institute of Chicago
12. School of Visual Arts, New York
13. Rhode Island School of Design

Portrait photography Tips-Lens differences can change facial impressions