The Metabones BMPCC Speed Booster SUPER16 0.58x F-Mount to MFT-Mount Lens Adapter mounts F-Mount lenses on an MFT-Mount camera body. Its optical group compresses the image circle to 0.58x, which widens the field of view and adds one and two-thirds stops of light. An aperture ring on the adapter sets the diaphragm, which keeps a lens with no aperture ring of its own controllable. A tripod foot carries the weight of the lens instead of hanging it off the camera mount.