What are the basic knowledge and skills of photography?

First, the basic knowledge of photography

1, the wider the light source, the softer the light. Conversely, the narrower the light source, the harder the light.

A wide range of light sources can weaken shadows, reduce contrast and suppress textures, while a narrow light source has the opposite effect. This is because the wider the light source, the more directions the light shines on the object, which will increase the lighting in the scene and reduce the shadows.

Tip: Arrange the portrait theme next to a big bright window to avoid direct sunlight. Windows can play the role of soft boxes, and the studio does not need special equipment.

The closer the light source is, the softer the light is.

Conversely, the farther the light source is, the harder the light is. This is because the closer the light source is to the subject, the bigger it is, and the wider it is; The farther the light source is from the subject, the smaller it is, that is, the narrower it is.

Take the sun as an example. The diameter of the sun is 109 times that of the earth. It's a fairly wide light source! However, the sun is 93 million miles away from the earth (about 65.438+0.5 billion kilometers), accounting for only a tiny part of the earth's sky, so the light is very hard when the sun shines directly on objects.

Tip: When you shoot a portrait indoors with existing lighting, you can change the distance between the light source and the subject to make the light of the photo more moving.

3. Diffuse reflection can disperse light, making the light source wider and the light softer.

The essence of using diffuse scattering to disperse light is to broaden the light source, so as to achieve the purpose of softening light. When clouds block sunlight, the shadow on the object will be obviously reduced, and if there is fog, the shadow will disappear. Clouds, gloomy skies and fog will diffuse light, and diffusion will spread light in all directions. On cloudy and foggy days, the whole sky will become a very broad light source and a natural soft box.

Tip: materials such as translucent plastic or white fabric can be used to diffuse strong light. You can add a soft mask in front of the artificial light source, such as the flash in the studio; If you are in bright sunlight, you can also use a hood or soft box to soften the light.

4. Reflect diffused light

Shooting a narrow beam on a large frosted surface (such as a wall, roof or frosted reflector) will spread to a wider area when reflected.

Tip: Knead a large piece of aluminum foil into a ball, spread it out and wrap it on a piece of cardboard, and a soft light reflector will be made. Although the diffusion effect of this self-made reflector is not as good as that of the white matte reflector, it can add shiny spots to the photos.

5. The farther the light source is, the faster the light decays and the darker the subject is.

For example, the distance from the light source to the subject increases by 1 times, and the light falling on the subject is only a quarter of that before the distance increases. The light will decay rapidly with the distance from the light source. This rule should be remembered that if you want to move the light source or subject, you must change the quality of the light.

Tip: When shooting portraits outdoors in bad weather, you should use a flash (hot boots or pop-ups), which can eliminate the shadow on the face of the person and will not affect the exposure of the background, because the light emitted by the flash can be ignored when it reaches the background.

Second, shooting skills

1, taking a long focal length lens as the main shooting lens (120 camera is about 250mm lens or 135 camera is about 135 mm lens), and taking its short depth of field function.

2. According to the principle of portrait formula composition method, close-up, half-length, seven-point or full-body composition can be taken directly, about 5-8 steps away from the subject.

3. During exposure, according to the characteristics of portrait photography, the aperture compensation of 1 ~ 2 should be turned on to make the facial texture brighter. The light on people's faces is soft and bright, which is the focus of this kind of photos.

4. In order to create bright eyes, it is best to place a reflector or whiteboard in front of the portrait to make the eyes reflect bright spots.

5. When printing, it is best to follow the post-processing skills and printing soft focus treatment to completely soften the skin, which can achieve the soft effect of the whole photo.

Photographic terminology

1, image depth

The distance between two imaging planes where the front boundary of depth of field and the back boundary of depth of field are conjugated respectively. Image depth corresponds to the depth of field, and the greater the image depth, the greater the depth of field. Criteria for determining the depth of field: 135 The diameter of the blur circle allowed by the camera is generally 1/30mm, that is, 0.033 mm ..

2. hyperfocal distance:

When the lens is focused at infinity, the scene at infinity forms a clear image, and at the same time, the object at a certain point at a limited distance can reach a clear standard, and the object near this point is blurred, so the distance between this object and the lens is hyperfocal distance.

3. Focal length:

The distance from the center of the lens to the focus. The unit of focal length is usually expressed in mm (millimeter). The focal length of the lens is usually marked in front of the lens, for example, f=50mm (this is what we usually call a "standard lens" because its viewing angle is the same as that of the human eye), and the focal length of 28-70mm (our most commonly used lens) is most suitable for taking portraits, 70-210 mm.

4. Aperture:

A device that controls the amount of light passing through a lens. The aperture is represented by f, including f 1.0, f 1.4, f2.0, f2.8, f4.0, f5.6, f8.0, f1,f 16 and f22.

Refer to the above? Baidu encyclopedia-photography