In photography: What is a dispersion circle?

Scattering circle is also called fuzzy circle, mixed disk or mixed groove circle. It is the spot formed by the dispersion of some image spots after the lens or lens is focused. After we pick up the camera and focus, the front or back of the focal plane is not the focus of the beam, but the spot that we can't see clearly, which is what we call the dispersion circle. This is determined by the physical characteristics of the camera lens. As we know, a photographic lens is a distant scene, and it is impossible to focus all the objects on one plane.

Due to the limitation of human eye resolution, the diameter of the dispersion circle is less than a certain length, and it can still be regarded as a point. The limit of the diameter of the dispersion ring is usually called its allowable value. Generally, the allowable value of interesting circle of dispersion is the indistinguishable length of ordinary eyes, which is about 0.1mm. Because the imaging distance is different from the clothing distance, the circle of dispersion formed by an object through a camera lens is usually less than 0.1mm.. The allowable value of 135 camera lens dispersion circle is. The allowable value of lens dispersion circle of. 1 or 0.05 mm, 135 camera is strictly limited because l 35 film is used for high magnification.