Metabones Leica R to BMPCC Speed Booster in Black Matt (p/n MB_SPLR-BMPCC-BM1). Leica R to Micro-4/3 mount Speed BoosterTM  adapters designed exclusively for the Blackmagic Pocket Cinema Camera (BMPCC). Note that this new 0.58x Speed Boosters will only attach to BMPCC equipped with a Micro-4/3 mount.  They cannot be attached to standard Micro 4/3 cameras.
 The new 0.58x Speed Booster reduces the crop factor of the BMPCC from 2.88x to 1.75x, and produces the largest aperture optics currently available, with a maximum output aperture of f/0.74.  For example, a 50mm f/1.2 now becomes a 29mm f/0.74 (i.e, by using 50mm lens, the actual focal length in BMPCC is 29mm x 3.02 = 87.58mm), and the Sigma 18-35mm f/1.8 becomes the world’s fastest zoom lens at 10.5-20.3mm f/1.0 with stunningly sharp performance. (i.e, by using 18-35mm lens, the actual focal length in BMPCC is from (10.5mm x 3.02 = 31.71mm) to (20.3mm x 3.02 = 61.31mm).