The EOS R system introduced RF lenses with a control ring around the lens body in addition to the usual focus and zoom rings. It controls a range of functions, from basic exposure to autofocus and image settings.
The position of control rings is different on different Canon leness, making it more difficult to find instinctively if you use a range of lenses. In this respect, using EF lenses with the control ring mount adapter is better as the control ring remains in the same location.
Some of the compact Canon RF lenses have little space for an additional ring and feature a combined focus and control ring. Autofocus on the EOS R series is so reliable there’s little need for a manual focus ring, so using it as a control ring is more useful.
When using automatic exposure modes, you may find a good use for the control ring to change one AF method to another. The benefit of the control ring is that you can switch back and forth by turning the ring in opposite directions, which is faster than cycling through all the available AF methods.
If you regularly shoot with Manual exposure mode, it is good to have separate controls for the individual parameters: shutter speed, aperture, ISO and exposure compensation when using auto ISO. For such use, assign exposure compensation to the control ring. The control ring can be set to only change a value while the shutter is half-pressed or even locked with a configuration of the lock button on most cameras.
Picture styles and white balance
If you like to work with JPEGs, it’s more important to choose appropriate white balance and picture style settings. The control ring can be set to freely cycle through these or require that the shutter is half-pressed before making a change.
Colour consistency is vital for video, so many movie makers use Kelvin white balance so that when edits are put together, there are no color shifts in the same light situation. Select Kelvin White Balance and then use the control ring to easily adjust the Kelvin value in response to changing light temperature.
Control rings and other customized button settings additionally make the camera more usable if you have limited movement or grip in your hands.
You might also like to read our guide on the best Canon camera, which covers the best DSLRs, mirrorless cameras and EOS-M cameras.
