Exploring Canon's intelligent autofocus system

How does Canon's intelligent autofocus work, which Canon cameras use deep learning AF, and how can this latest Canon autofocus technology help you to capture better shots and improve your hit rate?

Originally developed for the Canon EOS-1D X Mark III, the intelligent autofocus system with deep learning algorithms is also present on the Canon EOS R5 and Canon EOS R6. Wedding, fashion and portrait photographer and Canon Ambassador Félicia Sisco has already found it invaluable.

"It was crazy, with wedding guests jumping up and down all over the place," Félicia says of a recent assignment. Such a scenario might sound like an autofocus nightmare, but Félicia's Canon EOS R5 never missed a beat. In fact, she has been impressed with the EOS R5's AF since her first experience with it. "The first time I used the EOS R5 was for a very difficult fashion shoot with lots of movement," she says. "The autofocus was incredible. Now I'd feel lost without it." Félicia has also used the Canon EOS R6, which utilises the same deep-learning artificial intelligence autofocus system.

Canon Europe Professional Imaging Product Specialist Mike Burnhill explains that this latest iteration of the EOS iTR AFX system uses 'deep learned' artificial intelligence. The system is based on an algorithm that teaches itself by scanning millions of images. The system essentially learns how to recognise the heads of people, even if they're skiers wearing goggles, racing drivers wearing helmets, or gymnasts upside down or even facing away from the camera. Deep learning is a huge leap forward from the intelligent autofocus systems of previous Canon cameras.

At the busy wedding shoot using the Canon EOS R5 and EOS R6, Félicia was delighted at how the autofocus system is every bit as good in both cameras. "I love that the cameras have autofocus points everywhere, across the whole frame," she says. "I no longer need to line up the eye of a person with a particular AF point in the camera. The system automatically detects the face and the eyes and jumps straight to them."

Over a career spanning 40 years, Félicia's favourite lenses have long been the Canon EF 50mm f/1.2L USM and EF 85mm f/1.2L II USM primes, particularly in situations where an ultra-tight depth of field demands critically accurate focusing. "Photographers using older kit have told me they have problems autofocusing with these lenses and getting consistent results. I show them the Canon EOS R5 with the RF 85mm F1.2L USM lens and there's no longer a problem."

Autofocus tracking works with spectacular speed, accuracy and consistency in both face-detection and eye-detection modes. "I was shooting a model on a swing, so she was moving backwards and forwards, as well as up and down," says Félicia. "Autofocus instantly locked on to her eye and tracked her flawlessly as she moved."

In addition to eye and face-tracking abilities, the EOS R5 and EOS R6 add body and animal detection. Again, millions of existing images needed to be scanned to build up a sufficiently large database. It was a particularly complex task, says Mike. "Just for dogs, you could have a Chihuahua or a Great Dane. If you didn't know they were the same species, would you put them together? Then there are birds. You've got a hummingbird and an ostrich, an owl and a penguin. They're very different shapes, but they're all birds."

The technology rises to the challenge, as wildlife photographer Robert Marc Lehmann attests: "Everything that was hard to achieve for the last couple of years in terms of [photographing] moving animals just became very easy. This is going to be the game-changer for wildlife photography. Even with a sea eagle in flight coming from 100 metres away, the autofocus locks on and keeps [the subject] in focus all of the time. Even during intense turns and everything, it keeps it totally in focus. I just have to press the shutter button and rush out images at 20 frames per second."

Some of Félicia's favourite shots are taken in very low lighting conditions or even in near darkness. She sometimes partially closes curtains when shooting indoors to further reduce the light, or shoots outdoors at night, all without the use of flash. "Whether there's light or no light, the autofocus just works," she says. "I don't need to worry, just shoot, and everything stays sharp." Indeed, with Félicia's Canon RF 85mm F1.2L USM lens, the Canon EOS R5 can autofocus in light levels as low as -6EV, equivalent to shooting in the dead of night under a half-moon.

For capturing the definitive moment, Mike says that intelligent autofocus gives you one less thing to worry about. "Taking a photograph is like juggling. You've got to balance focus, composition, timing and exposure. It's much easier to juggle two balls rather than three. With intelligent autofocus we're taking away one of the balls, so you don't have to concentrate on so many things. It makes things easier and less tiring, and you can get better results."

To sum up, Félicia says that the autofocus performance and reliability of the Canon EOS R5 and EOS R6 enable her to devote all of her attention to composition and timing. "I shoot with both eyes open. I want to share the emotion and to capture it. I have to be able to trust the camera in my hand as if it were part of me, and I trust the EOS R5 and EOS R6 implicitly. I can simply shoot and know that I'll get the results I want without worrying about technical problems."