The Vizelex Macro Focusing Helicoid from FotodioX allows a Canon EOS lens to be used as a macro lens with variable magnification ability. It features a leaf spring design to hold the lens tightly to the camera body, ensuring there is no play between the camera and the lens. The helicoid features an all-metal design and a polished surface. Although the lens will fit physically, automatic diaphragm, auto-focusing, and other functions will not operate correctly while using this adapter. Use "stop-down mode" when metering since the lens aperture can not be controlled by the camera. You can shoot with manual mode or aperture priority mode.