In fact, it is very good to explain: "White plus black reduction" is also necessary to see the situation. Take the moon as an example. We shot at night. Although the moon is
bright (can be seen as white), the big environment is very dark (can be seen as black). And the proportion of the moon occupying the picture is not large, if we shoot normally, it is the effect below.
Shooting the moon is not the same as taking a snow scene. The moon is shot at night. There is basically no reflected light. There is not much light entering the camera, so the camera will increase the exposure by extending the exposure time. When we shoot snow scenes, generally during the day, the overall brightness is very high, the reflection is also strong, the camera will shorten the exposure time to reduce the exposure, often there mini tripod for iphone will be underexposure, the snow is not white, so increase the exposure compensation To make the snow white.