In photography, who can tell me what is light ratio or main and auxiliary light?

In fact, simply speaking, the light ratio reflects the contrast between light and shade on the subject. Large light means obvious contrast between light and shade, and vice versa.

The main light is actually the light that mainly depicts characters, and what kind of light and shadow structure is generally determined by the main light. Determine whether there are auxiliary lights according to personal needs.

Extended data:

Equipment used

Generally speaking, people take pictures with visible light, and cameras are the most commonly used. Because of different scenes and uses, cameras have many classifications. Generally speaking, a camera must have several basic components to ensure the exposure process, including: photosensitive medium, imaging lens, exposure time control mechanism, film cassette, storage medium, electronic photoreceptor and electronic storage medium.

Exposure process

When taking pictures, light enters the cassette through a small hole (more often, a lens group) and forms an image on the medium on the back of the cassette (relative to the incident direction of light). According to the actual light intensity and the photosensitive ability of the medium, the required light time is also different. In the process of illumination, the medium is irradiated by light.

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