Leica S-series lenses are not part of the L mount alliance. However, with the Leica original adapter ring, it can be used on Leica SL and SL2 cameras with full functions, including aperture-controlled autofocus. On Panasonic full-frame mirrorless S1R \ S1 cameras, the body can control the aperture, but not autofocus. Manual focusing is possible; on Sigma's new FP, neither autofocus nor aperture can be controlled. In fact, it cannot be used. Whether the full-featured use of Leica S-series lenses on this model will be awaited by Sigma. The company updates the firmware.