What is the principle of finding the relationship between aperture and depth of field?

The larger the aperture, the smaller the depth of field; The smaller the aperture, the greater the depth of field;

(2), the lens focal length

The longer the focal length of the lens, the smaller the depth of field; The shorter the focal length, the greater the depth of field;

(3), shooting distance

The farther the distance, the greater the depth of field; The closer the distance, the smaller the depth of field.

Principle: in a photo, the focus is the clearest, and it is relatively clear to leave the focus a distance forward or backward. This distance is the depth of field. The above three elements are all comprehensive. If you want to get the maximum depth of field, use "hyperfocal distance": focus on the near boundary of the depth of field when the aperture and focal length are fixed. For example, the depth of field ranges from A to B, the focus is C, the distance from the camera to point A is D, A is close to the camera, and B is far from the camera. At this time, the focal length and aperture are unchanged. If you focus on point A, the depth of field will be expanded to D/2 to B. ..