Mr. Ding Contax G to Canon RF Adapter

The Mr. Ding Contax G to Canon RF Adapter lets Contax G rangefinder lenses sit on Canon EOS R bodies. Mr. Ding Studio sells it from its official store for 169 dollars; it weighs 75 grams and carries a focus ring that drives the lens focus coupling.

Contax G lenses were built for an autofocus rangefinder and most of them have no focus ring at all. The adapter solves that with its own ring and adds a chip that talks to the body: the camera shows focus confirmation through Canon's focus guide, trap focus can wait for a moving subject, and the model, focal length and maximum aperture of the selected lens are written into EXIF.

There are limits worth knowing. Aperture is not controlled from the body, so correct exposure comes from shooting at the lens's maximum aperture; the adapter reflects that aperture and three one-third stops below it, and past f/8 the meter goes wrong. Electronic confirmation and trap focus do not work on the EOS R10, R50 and R100, which lack the focus guide menu. With the G21 and G28, fit the lens to the adapter first and then the pair to the camera with the camera off, because their rear elements protrude.

For anyone keeping Carl Zeiss Contax G glass, the Mr. Ding Contax G to Canon RF Adapter brings back something close to a native lens: focus by turning a ring, with the camera confirming the point. Warranty runs twelve months and economy shipping is free. An adapter like this makes sense on bodies with a focus guide, not on the entry-level models.