I have fuji x-t2 and leica m5 with bunch of lenses. I got kipon adapter for around $50, and while adapter is okay, I don’t think that fuji is any good digital back for leica system. Partially it’s because of crop factor, and the fact that my zm 21/4.5 or 35/2.8 are not what they are on leica. But mostly it’s because fuji sensor is not optimized for leica glass.
Both zm 21/4.5 and zm 35/2.8 have poor edge/corner performance which doesn’t get really flat even stepped down. Sharpness of both lenses is surpassed by fuji 23/1.4 and 35/1.4, on all apertures.
Cv 35/1.4ii and cron 50/2 are slightly better in the corners, but sharpness wise across the field and in the center they can’t quite get to fuji 35/1.4 and 50/2, again on all apertures.
What makes all leica lenses harder to use on fuji is short focusing throw. Lenses lice 35/1.4, 50/2, 90/2.8 take sub-mm barrel movement to focus precisely wide open. Focus by wire that native lenses have, even though without great feedback, is much more useful to operate if you use lenses on fast apertures. Because of focus throw, or maybe because all my lenses were optimized for film, it feels that the focus point is really diminishing and depth of field is razor thin.
Fuji has rather high pixel density, equivalent FF sensor would have ~60 MP, and it really is optimized for modern lenses. Old era lenses just don’t have that appealing compared to what fuji has to offer. Most lenses are simultaneously sharper, faster (aperture), faster to work with (AF), and have really nice rendering. Lenses from leica immediately fall under “special effect lenses” on fuji, at least for me.
