In addition to a larger diameter mount and additional contacts, one of new features of Canon's RF lenses—and one of its EF to RF adapters—is the Control Ring, a physical dial around the perimeter of the lens that can be customized to control various camera functions including aperture, ISO and shutter speed.

By default, the Control Ring is adjusted in predetermined steps, which click into place while rotating the ring. While this is beneficial when you need a tactile indication of how many steps you've adjusted various settings, it does cause a bit of movement and noise, which isn't helpful if you're filming video.

An illustration provided by Canon showing off the Control Ring on its RF 35mm F1.8 IS Macro lens.

Canon is addressing this problem by offering a de-clicking service for RF lenses. According to a pricing sheet, Canon will charge $79.99 to de-click any RF lens and $59.99 to de-click the Control Ring Mount Adapter EF-EOS R, not including the cost of taxes and shipping. Once de-clicked, the lens or adapter will be able to be switched between its default functionality and the de-clicked mode.

The service can be scheduled via Canon's customer service phone number (1-800-652-2666) or its online support page.