Turns out fotodiox has this tilt/shift adapter for most medium format lenses to the RF mount. Mine arrived today.

I was happy to have it confirmed that focus peaking in the R5 works with the adapted Mamiya lens and, a quick test:


Mamiya 645 80 mm f/1.9 @ f/1.9 no adjustments:
Name: R5 Tilt Shift RKR-1-3.jpg Views: 198 Size: 190.9 KB



Same settings, tilted down:
Name: R5 Tilt Shift RKR-2-2.jpg Views: 199 Size: 144.7 KB


I played around with the shift feature as well, I did not notice any strong vignetting.

Could be a nice way to get wide aperture, longer focal length tilt-shift lenses. Keith Cooper did a review.

Fotodiox also offers a "Rhino Cam Vertex" where you mount the adapter to a tripod, then pivot the FF camera mounted to the adapter in a circle taking 4 images. These images can then be stitched together to replicate the image circle of various MF lenses. Interesting idea.