M4/3 was introduced in 2008 by Panasonic and Olympus. It attracted some users who shoot basically with the 35mm system, and they finally switched to the new system or used it as a spare system. However, some new users thought that the M4/3 lens with matching equivalent focal length does not share the same perspective. For example, when someone uses a 17mm lens on the M4/3, he feels that the angle of view is quite different from the 35mm lens of the 35mm system. They thought, “because that’s the perspective of a 17mm lens.