What's the difference between a camera 4mm6mm8mm?
The difference between 4mm, 6mm and 8mm cameras is that the viewing angle is different. The smaller the number of mm, the larger the area at the same distance.
The 4mm, 6mm, and 8mm of the camera refer to the focal length of the lens. Focal length, a measure of the concentration or divergence of light in an optical system, refers to the distance (also known as the image distance) from which the parallel light travels from the optical center of the lens to the focal point of light collection. In a video camera or camera, the focal length (or image distance) refers to the distance from the center of the lens to the imaging plane such as the CCD or CCD.
mm is the aperture of the lens, which is what we often say. The number of millimeters is not as large as possible. The smaller the lens, the wider the picture. The larger the lens, the narrower and clearer the picture. The picture is partially enlarged, and the angle and distance of different focal lengths are different.
The relationship between the focal length and the field of view of the lens is: the longer the focal length of the lens, the smaller the field of view of the lens. In addition, when the lens focal length is constant, the relationship between the lens specification and the field angle of the lens is: the larger the lens specification, the larger the field angle of the lens.
Depth of field (DOF) refers to the range of the front-to-back distance of an object as measured by imaging at the leading edge of a camera lens or other imager. The distance between the aperture, the lens, and the subject is an important factor affecting the depth of field.