How to understand the sensitivity and exposure in professional mode when taking photos with mobile phones? What do they have to do with the brightness of light?

The "sensitivity" and "exposure" in this so-called "professional mode" are just unprofessional concepts.

If there is still the word "exposure" in the field of photography, then the word "photosensitive value" is relatively strange. However, the concept of "sensitivity" is a very professional concept.

Of course, when it comes to exposure and sensitization, although these statements are not very professional, people who know photography can fully understand the meaning. ...

About sensitivity, it is the sensitivity of the image sensor (film) of the camera to light. In the field of photography, "sensitivity" is used to define this concept. At low sensitivity, the image sensor (film) is less sensitive to light, but the image quality is purer. In the high-sensitivity state, the image sensor (film) is more sensitive to light and can clearly image in the dark. However, the consequence of this is that the noise increases and the image quality deteriorates.

About exposure, it refers to the degree of exposure when the photo is released ... normal light and dark state means accurate exposure. The light and shade are not normal. If it is too bright, it is overexposed; If it is too dark, it is underexposed.

Exposure indication information can be seen in the viewfinder of a professional camera, and users can know whether the current state is underexposed or overexposed according to the exposure indication information, so as to adjust the setting of shooting parameters in time and obtain a more accurate exposure state.

As for the sensitivity, more is to use the auxiliary state to obtain a more accurate exposure state ... When the light is sufficient, use low sensitivity to obtain pure image quality. Using high sensitivity in dark light can obtain relatively accurate exposure state, at the cost of losing a certain degree of image quality.