M, the diagonal viewing angle is equivalent to the focal length of 38- 1 15mm of the traditional 35mm camera. Generally speaking, the standard lens focal length of a 35mm camera is about 28-70mm, so if the focal length is higher than 70mm, it means that the telescopic effect is supported. If it is less than 28mm, it means that it has wide-angle shooting ability. "Focal range" is the extension of focal length, which is usually divided into general shooting distance and close-up distance. The general shooting distance of a camera is usually marked as "from a certain centimeter to infinity", and products designed by advanced technology often provide close-range shooting function (macro) to make up for the problem of not focusing in general shooting mode. Some cameras emphasize the magical ability of supporting 1 cm close-up, which is suitable for shooting fine objects.