Canon EF to RF Adapter Autofocus

Key Takeaways

• EF lenses work flawlessly on Canon RF-mount bodies using the official Canon adapter.
• Autofocus improves moving from old DSLR to mirrorless.
• Canon’s adapters preserve image quality and functionality, no glass is added unless you use drop-in filter models.
• The control ring version of the adapter replicates RF lens functionality on old EF lenses
• Third-party adapters can save money but may introduce minor issues like lens flare or reduced build quality.
• You can’t adapt RF lenses to an EF mount camera. The compatibility only works one way.

Canon’s leap into the mirrorless scene has brought with it a nifty solution for those who’ve collected Canon EF glass over the years.

This solution is the Canon EF to RF adapter. These adapters are lifesavers for those of us transitioning to the mirrorless system without wanting to abandon our collection of EF lenses.

The most basic, and budget-friendly, is the standard Canon EF to RF Adapter. It’s a no-frills option that does its job perfectly, maintaining the original quality of your lenses.

If you want the functionality of the control ring that the new RF lenses offer, the Canon EF to RF Adapter with Control Ring is the adapter you should look at. It replicates the programmable control ring feature found on RF lenses, letting you adjust settings like aperture or ISO right from the lens (or in this case the adapter).

Personally I find the controls on my R5 sufficient for quick adjustments, but people adapting to camera bodies without dedicated controls for shutter speed, iso and aperture might find this feature helpful.

Lastly, there’s the Canon EF to RF Adapter with Drop-In ND filters. This would be a good option to look at if you like to shoot with ND filters or polarizers. What’s really cool is this adapter allows the use of a single set of ND filters across all your lenses, which is a fantastic cost saver and more convenient then having to get a set for each lens.

The only downside to this adapter is the mandatory clear filter when you’re not looking to use the ND option, introducing an extra element that will affect image clarity.

Canon EF-EOS R Adapters

The following are the three EF to RF adapters that Canon offers.

• EF to RF Adapter (B&H) 
• Adapter With Control Ring (B&H)
• Adapter with ND filter (B&H)

Venturing beyond Canon’s official gear, many photographers, myself included, have explored third-party options for EF to RF adapters. Among these, Vello and Commlite are prominent names, but all 3rd party adapters come with their quirks.

Vello’s adapter caught my attention with its good autofocus performance and clarity. However, like most aftermarket adapters, it lacks the internal bellows found in Canon’s adapter, leading to halo effects when shooting in bright conditions.

It’s a noticeable drawback for those of us keen on preserving the original quality of our EF lenses.

Pros and Cons of EF to RF Adapter

When I transitioned to a mirrorless system, the Canon EF to RF adapter autofocus became an essential part of my kit. I had built up a solid collection of EF lenses over the years, and I was genuinely concerned about whether they’d work well with my new camera.

To my surprise, not only did they mount without issue, but they also performed better then they did on my old camera bodies.

When I say they got better I specifically mean that the auto focus speed and accuracy of my lenses became night and day better.

The improved speed and accuracy were immediately noticeable, and I didn’t feel like I was compromising on image quality or functionality.

While native RF lenses are still optimized for the mirrorless system and offer some clear advantages, being able to rely on my trusted EF glass made the transition far easier and more affordable.

That said, using an adapter isn’t without its limitations. Below, I’ve outlined the key pros and cons of using an EF to RF adapter with your Canon mirrorless camera.

Pros

1. Expanded Lens Compatibility: The most significant advantage is the ability to use your existing collection of EF lenses with a new RF-mount camera system. This is particularly beneficial if you’ve already invested in high-quality EF lenses.
2. Cost Savings: Instead of buying new RF lenses, which can be expensive, you can continue to use your EF lenses, saving money in the short term.
3. Improved Autofocus: Good quality adapters will improve both the speed and accuracy of your old EF lenses by taking advantage of the new mirrorless camera’s autofocus system.
4. Additional Features: Some adapters, like the Canon Control Ring Mount Adapter, add functionality, which is present on native RF lenses but not on EF lenses.
5. Preservation of Image Quality: High-quality adapters do not introduce additional glass elements between the lens and the sensor, thus maintaining the original image quality of the lens.

Cons

1. Potential for Reduced Performance: When compared to native RF lenses on mirrorless bodies, adapted EF glass will not perform as well.
2. Extra Bulk and Weight: Using an adapter adds extra length and weight to your camera setup, which can make it slightly more cumbersome.
3. Compatibility Issues: Not all EF lenses may be fully compatible with all functions of RF-mount cameras when using an adapter, potentially limiting certain features.
4. Cost of Good Adapters: While cheaper than buying new lenses, high-quality adapters can still be a significant investment, and opting for less expensive, lower-quality adapters may introduce issues like poor fit or build quality.
5. Potential for Flare: Some users have reported increased lens flare when using certain 3rd party adapters, due to less effective designs of the internal chamber.