What is the function of photographic aperture size? 0? three

The function of the aperture is to determine the amount of light entering the lens. The larger the aperture value, the more light enters. On the contrary, the smaller.

The English name of Aperture is aperture. Aperture is a device used to control the amount of light entering the photosensitive surface of the fuselage through the lens. It is also an extremely important index parameter of the camera. It is usually in the lens, and its size determines the amount of light that enters the photosensitive element through the lens. F is used to represent the pore size, and the formula is as follows:

Aperture f value = lens focal length/lens aperture diameter.

As can be seen from the above formula, to achieve the same aperture f value, the aperture of a long focal length lens is larger than that of a short focal length lens.

It is worth mentioning here that the smaller the f value of the aperture, the more light enters in the same unit time, and the light entering amount of the upper level is exactly twice that of the lower level. For example, if the aperture is adjusted from f8 to f5.6, the amount of light entering will double. We also say that the aperture is enlarged by one level. For consumer digital cameras, the aperture f value is often between f2.8-f 16. In addition, many digital cameras can adjust the aperture by 1/3.

The smaller the value after f, the larger the aperture: the role of the aperture is to determine the amount of light entering the lens, and the larger the aperture, the more light entering;

The larger the value after f, the smaller the aperture: in short, under the condition of constant shutter, the larger the aperture, the more light enters and the brighter the picture; The smaller the aperture, the darker the picture.

Extended data:

Purpose of using aperture priority mode

The purpose of using aperture priority mode is that users can control the depth of field by themselves. In landscape photography, users need to set a smaller aperture when they want clear image quality near and far and shutter speed is not important. In figure photography, camera users prefer a larger aperture to make the background of the figure out of focus, so as to highlight the theme of the figure and dilute the background.

Another purpose of using aperture priority is to let the camera choose the shutter speed to prevent inappropriate exposure time. In landscape photography, users will choose a larger aperture value when shooting waterfalls, that is, a smaller aperture combined with a longer shutter time will blur the waterfalls. But when shooting in dim light, the smaller aperture value, that is, the larger aperture, makes more light enter the lens.

Baidu encyclopedia-camera aperture

Baidu encyclopedia-aperture priority