Magic Format Converter lets you use DSLR-lenses on the Fuji GFX 50S
(Digital Photography Review)

Venus Optics today announced the Laowa Magic Format Converter (MFC), an adapter which allows to use Canon and Nikon full-frame lenses on the Fujifilm GFX 50S medium format camera. It differs from currently available adapters in so far that it also corrects for the smaller image circle of the DSLR lenses, reducing vignetting and edge softness. The Magic Format Converter takes advantage of the short flange-back distance of mirrorless cameras and comes with internal optics that expand the image circle of the lens. According to the manufacturer this does not compromise the image quality but the adapter comes with a focal length multiplier of 1.4x and reduces the maximum aperture by one stop. Venus optics is currently for beta testers for its adapter. If you own a Fuji GFX 50S and are interested in trying the Magic Format Converter you can find more information and contact details on the Venus Optics website.