The Metabones EF-MFT T Speedbooster XL 0.64x Mark II is a focal reducer to be placed between MFT mount cameras and full frame EF mount lenses. A focal reducer reduces the lens’ focal length (it widens the lens) and increases the amount of light reaching the camera sensor. 

The Speedbooster XL is a focal reducer with a factor of 0.64. This means that a Canon EF-mount 50mm f/1.4 lens combined with this speedbooster has the same result as a native MFT 32mm f/0.9 lens. The Metabones EF-MFT T Speedbooster XL 0.64x Mark II also supports the electronic communication between camera and lens. Autofocus, stabilization and aperture control remain enabled. However, the speed of the signal can be slower than when using a native MFT lens. 

The EF-MFT Speedbooster XL 0.64 mark II is compatible with the Panasonic DMC-GH4, GH3, G3, G5, G6, G10, GF3, GF5, GF6 and GX1, the Olympus PEN E-PL7, the Blackmagic Cinema Camera and the Blackmagic Pocke Cinema Camera. It weighs 170 grams and has a detachable lens support with 1/4” thread. 

Attention! Even if your lens adapter supports autofocus, the speed of the autofocus might slow down compared to using a native lens.