When the Canon EOS R mirrorless system was launched with the new RF Mount, Canon also unveiled four different mount adapters that allow the use of older EF and EF-S lenses on the mirrorless EOS R cameras.

The first adapter was a basic adapter with no fancy features, and at $99 it’s the cheap option that is sometimes included with EOS R cameras as a freebie. Then there are two versions of the Drop-In Mount Adapter that either include a circular polarizer filter, or a variable neutral density filter. That’s a nice feature to have an an option, but both of those adapters are quite expensive.

The fourth mount adapter is the subject of this review: The Canon Control Ring Adapter EF-EOS R.

There are no optical elements in the adapter.

The Control Ring is a feature that can be found on all of the new native RF lenses for the EOS R system, and as the name suggests, the Control Ring Adapter adds this same feature to EF and EF-S lenses when used on an EOS R camera.

The control ring is a customizable ring that can be assigned control over shutter speed, aperture, ISO or exposure compensation. In addition to that, you can also decide whether you want to the ring to be operational at all times, or only when the shutter button is depressed half way so that it does not get accidentally changed.

Control Ring Adapter in use adding functionality to the EF 100-400mm L IS II.

The adapter itself is dust and moisture sealed just like Canon’s higher end cameras and L Series lenses, and it certainly feels like you can depend on it in the field.

Out of all of the EOS R mount adapters, this one is my favourite! Personally I absolutely loved assigning ISO to the control ring. It felt so natural to adjust aperture with the dial on the back of the camera with my thumb, shutter speed with the dial on the top of the camera, and ISO with the control ring. Once I used this setup and felt how fluid it all was, I knew there was never any going back and I purchased the adapter once I returned the loaner one I had for review.

If your kit includes both RF and EF lenses then I think the Control Ring Adapter will be a must purchase item. I cannot imagine having access to the control ring on some lenses but not others. That could really mess with your workflow and muscle memory.

Here you can see the control ring on the new RF 50mm f/1.2 lens
All Canon EF-EOS R mount adapters come with a small protective case.

The Control Ring Adapter is $199, and whilst that is double the price of the basic adapter I really do think it’s worth it. With ISO assigned to the control ring, it was so much easier to adjust ISO that I found myself experimenting quickly with lower and lower ISOs while I was shooting. This was giving me cleaner and cleaner images in a situation where I would otherwise probably have left the camera at one ISO value. I’m sure it has had a benefit to the quality of some of my images, and for that I’ll gladly pay the extra money over the boring basic mount adapter!

Where to buy

As always, it’s greatly appreciated when you use our links to make your purchases. We may make a small commission when you do this and it helps us bring you more content in the future. The adapter can be purchased at:

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