All imaging enthusiasts want their camera to function as if it is an extension of their body. In order to realize this wish, the EF lens adopted an innovative "fully electronic mount" that makes the operations between the body and the lens fully electronic eliminating the need for mechanical connections. When the mount is used, all data transferred between the EF lens and the EOS camera body is handled electronically. Autofocus communication links between the lens, and the body are maintained even when an extender is used, ensuring optimum operability and durability even in the most severe conditions. Canon’s large, 54mm diameter electronic lens mount provided the foundation for the design and production of the world’s brightest 35mm SLR camera lens — the EF50mm f/1.0L USM. This large-aperture lens can achieve fine detail and an attractive background blur (bokeh) even in candlelight, expanding the potential range of photographic expression. The large-diameter electronic lens mount design also facilitates the development of new lenses for the EOS R system, such as single-focal lenses with large apertures and zoom lenses with higher magnification power.
