What is the function of aperture in photography?

The main function of the aperture is to adjust the amount of light received by the image sensor. When you increase the aperture, more light enters the camera. When you narrow the aperture, less light enters the camera. Just remember a rule: the larger the aperture, the more light enters, the brighter the photo will be, and the smaller the aperture, the less light enters, the darker the photo will be.

You can adjust the amount of light entering the lens. For example, domestic kittens always shrink their pupils into a line during the day, and automatically Zhang Kaicheng a round hole at night. So in the same way, when taking pictures, the aperture should be narrowed when the light is strong, and the aperture should be opened when the light is dark. That is to say, the smaller the F value (other parameters remain unchanged), the more favorable it is for shooting at night.

Aperture is the most important factor to determine the depth of field. Small aperture (large aperture value), depth of field, large aperture (small aperture value), depth of field! For example, nearsighted friends, if they don't wear glasses, always habitually squint at things, so they can often see things clearly. To use photographic terminology, this is called: narrowing the aperture (pupil) and increasing the depth of field!

Extended data:

The shutter speed controls the duration, while the aperture allows you to adjust the volume. The larger the aperture diameter, the greater the amount of light flowing through the camera lens, so that the aperture size can be controlled. Different lenses have their own aperture setting range. If you have ever checked the specifications of a camera, you will undoubtedly see alphanumeric symbols like f/ 1.4, f/5.6 and f/22.

Each of these numbers is associated with a specific lens aperture size or f-stop. The aperture number is a fraction, which tells you the exact diameter of the aperture at a given aperture setting. However, this system is somewhat counterintuitive, because smaller numbers represent larger apertures and larger numbers represent smaller openings.

Aperture and shutter take precedence.

In addition to providing automatic mode, high-end digital cameras usually have two options: aperture priority and shutter priority, so that you can decide a certain aperture value or a certain shutter value on some occasions, and then match the appropriate shutter or aperture respectively to present different depth of field (sharpness) or effects.

Aperture priority mode

After we decide the aperture f value ourselves, the camera metering system will automatically choose the appropriate shutter speed (which can be an accurate stepless shutter speed) according to the light conditions at that time. A digital camera with an exposure mode dial usually engraves an "A" on the dial to indicate the aperture priority mode. Aperture priority mode is suitable for photography that emphasizes the depth of field effect.

Because the focal length of digital camera is much shorter than that of traditional camera and the aperture of lens is small, it is difficult to produce narrow depth of field. Some digital cameras have a special portrait exposure mode, which uses built-in programs and a large aperture to blur the foreground and background.

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