What is the relationship between aperture size, aperture value f and depth of field?

The larger the aperture, the smaller the aperture value f and the smaller the depth of field; The smaller the aperture, the larger the aperture value f and the greater the depth of field.

The smaller the value behind f, the larger the aperture, the more light entering, the brighter the picture, the narrower the focal plane and the more blurred the background of the subject;

The larger the value behind f, the smaller the aperture, the less light entering, the darker the picture, the wider the focal plane, and the clearer the front and back of the subject.

Three elements of depth of field: aperture, lens and object distance are important factors affecting depth of field;

1, the larger the aperture (the smaller the aperture value f) and the shallower the depth of field, the smaller the aperture (the larger the aperture value f) and the deeper the depth of field.

2. The longer the focal length of the lens, the shallower the depth of field, and vice versa.

3. The closer the subject is, the shallower the depth of field is, and the farther the subject is, the deeper the depth of field is.

Extended data

The function of aperture

1, which 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.

The adjusting ring on the rotating lens or the knob on the digital camera body is used to adjust the aperture size.

2. 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!

Baidu encyclopedia-depth of field

Baidu encyclopedia-aperture