What is a depth of field lens?

Depth of field lens is a kind of long lens. It's a technical term for film and television photography.

Camera depth of field:

When the lens of a camera is clearly focused on an object, the points on the same plane perpendicular to the lens axis at the position opposite to the lens center can be quite clear images on the film or receiver, and the points in a certain range before and after the lens axis on this plane can also form relatively clear image points acceptable to the eyes. The distance between all the scenes before and after this plane is called the depth of field of the camera.

Three determinants of depth of field:

1, lens focal length

2, the main distance

3, the size of the aperture

Aperture, the distance between the lens and the subject are important factors affecting the depth of field;

1, the larger the aperture, the smaller the depth of field, and the smaller the aperture, the greater the depth of field.

2. The longer the focal length of the lens, the smaller the depth of field; Conversely, the greater the depth of field.

3. The closer the subject is, the smaller the depth of field is, and the farther the subject is, the greater the depth of field is.

The shorter the focal length of the lens, the wider the range of depth of field, the smaller the aperture and the greater the depth of field. A super wide-angle lens has a great depth of field at almost all apertures. Even with the smallest aperture, the depth of field of telephoto lens is very limited. Some single-lens reflex cameras have a depth of field prediction button, so you can predict the depth of field before pressing the shutter.