What is the use of SLR camera exposure?

In photography and camera terminology, exposure is ISO.

The lower the ISO, the less noise there is in the photo, and the cleaner and more transparent the photo is. But at the same time, the more total exposure is needed, the longer the exposure time is, and the larger the aperture is needed.

When the light is dark, low ISO shooting will blur the picture because of long exposure time and shaking hands. After upgrading ISO, the exposure time can be shortened to avoid shooting failure and poor image quality.

Every time the exposure value increases 1, the exposure will change by one step, that is, the exposure will be halved, for example, the exposure time or aperture area will be halved. This may cause confusion. The reason for the decrease, rather than the increase, is that the exposure value reflects the setting of camera shooting parameters, rather than the illumination of the film.

Extended data:

Exposure is an optimal exposure standard set by the manufacturer according to the photosensitive capacity, photosensitive tolerance and noise reduction of CCD when designing cameras, and the best photo quality can be obtained under this standard. When shooting, when the shutter is half pressed, the camera will set the aperture, shutter and sensitivity according to the light conditions at that time.

Under special circumstances, this setting may lead to improper exposure. If the background light is too strong or too weak, the subject will be underexposed or overexposed. At this time, it is necessary for the landlord to manually adjust the exposure compensation and increase or decrease the exposure accordingly, so that the subject can get the appropriate exposure.