What is the meaning of AE in SLR digital camera?

The abbreviation of automatic exposure control device.

Automatic exposure control means that the camera automatically determines the correct exposure aperture and exposure speed according to the set program under the condition of fixed light and sensitive film. AE modes can be roughly divided into four types: aperture priority AE, shutter speed priority AE, program AE and depth of field priority AE.

Aperture priority AE mode is an automatic exposure mode in which the photographer manually selects the aperture size when shooting, and then the camera automatically selects the shutter speed required for appropriate exposure according to the brightness of the scene, the sensitivity of the film or CCD, the manually preselected aperture and other information. Simply put, it is an exposure mode of "manual aperture and automatic shutter speed". The advantage of automatic exposure with aperture priority is that photographers can control the depth of field according to their own needs, so this exposure method is mainly used in shooting occasions that need to give priority to the depth of field, such as shooting landscapes, portraits or macro photography. When using aperture priority automatic exposure, the preview function of depth of field on the camera is effective, and it is also effective when adding various close-up accessories and reflective lenses, but the effect will not be ideal when shooting moving objects, TV pictures and computer pictures.

Shutter speed priority AE mode is an exposure mode in which the camera automatically selects the aperture size required for correct exposure according to metering information, CCD sensitivity and manually set shutter speed, that is, "manually adjust shutter speed and automatically set aperture". In this mode, the shutter speed manually selected and the aperture coefficient automatically set by the camera will be displayed on the LCD screen or camera.

Programmed AE exposure (P) is an automatic exposure mode, in which the camera automatically adjusts the aperture and shutter speed according to the program. This exposure mode is widely used in portable cameras (that is, fool cameras).

AE with priority of depth of field, also called DEP, is an automatic exposure method with priority of depth of field, especially suitable for taking group photos and landscape photos.

Some SLR cameras, if specially equipped with AE key, are generally used to lock the exposure value. That is to say, when you shoot the first scene for proper metering, press AE to lock its exposure value, and then go to another scene, and press the shutter halfway to focus automatically. Exposure value will not change, and it is mostly used in complex lighting environment.