One of the most advanced features found in Sony cameras is the Eye AF mode. In the latest Alpha cameras, Eye AF works in continuous servo mode which takes the feature from useful to tremendously powerful. Not only does Eye AF find the eye to establish focus, but it holds the eye as the camera and subject move and as you shoot at high frame rates. For wedding and portrait photographers, having the ability to lock onto an eye and hold it like this is a game-changer. 

Some call Eye AF a hidden mode because it’s programmed as custom function rather than being permanently assigned to a particular button or switch. This flexibility is a great benefit as it enables you to set Eye AF to start only when you want it and you can set it up on a button that makes sense with how you like to shoot. 

In this post we’ve collected a reviews and resources about Eye AF so if you haven’t used the feature yet, you can see how it works and learn how to set it up in your camera.

Starting with how it works, here are a couple of videos by DPReview.com that show Eye AF in action. DPReview’s tests are more stress tests that real-world shooting evaluations and they give you a good idea of how well Eye AF works under these super-demanding conditions.

“Here's where things really get interesting. The video [below] - shot through the electronic viewfinder using an iPhone - shows what the Sony α7R II is capable of with a native FE mount lens attached (FE 24-70 F4 OSS). That's continuous eye tracking, where the camera automatically finds the nearest eye, and continuously focuses on it, despite rather drastic and fast movement along the X, Y, and Z (distance) axes. No hunting, no jumping off to some other subject, just fast and effective AF on our subject's eye.

“We've certainly seen implementations of eye AF in other cameras: on many Panasonic and Olympus mirrorless offerings, for example. However, we've rarely, if ever, seen it combined with phase-detect AF for this uncannily fast and accurate AF.”

DPReview also tested the Eye AF feature in the RX100 IV. Again, putting the system through some particularly challenging tests, they found the system to be incredibly robust.

“Now that you've seen what the α7R II is capable of with regards to eye AF, we wouldn't blame you if you wanted something similar in every camera. Luckily, Sony offers a similar, rather compelling eye AF feature in continuous AF on the RX100 IV. And it's really, really good, especially when you consider the RX100 IV has a contrast-detect only AF system. In fact, it's the reason I'm planning on upgrading my RX100 III.

“Eye AF in continuous focus is new to the RX100 IV and RX10 II, and we have a feeling that what enabled it is the faster readout of the image sensor over previous models. Not only does this bring high frame rate and 4K video to these little cameras, but it also gives the focus algorithms more temporal data to work with. And looking at the speed which eyes are tracked, it certainly seems the camera is speedily taking advantage of this extra data.

“Of course the proof is in the proverbial pudding: the camera has to actually focus on the eye in addition to tracking it. And here the RX100 IV does not disappoint: every single shot is in focus on the eye, with the lens set wide open to F1.8, as you can see from the magnified views.”

To get Eye AF set up and working for you, here are a few videos showing where you can find the Eye AF mode and how to program it as a custom function.

Gary Fong offers a number of tutorial videos on using Sony cameras. One of the most useful aspects of Fong’s videos is how explains why he does things the way he does. In this video using the a7R II, Fong describes Eye AF in Continuous Mode as “more important than any other feature [Sony] has done.”

“In a large technological advance that would be of immense value to wedding photographers is the Sony α7R II's "Eye-AF" in Continuous (otherwise known as 'servo' mode) Autofocus mode.  

“This allows the photographer to have the camera pinpoint the iris of the eyeball even if the subject is in motion during shutter release or in a motor drive sequence.  This is an unprecedented feature.”

In this video, Fong shows how he sets Eye AF in the Sony α6300 and he shows it working in a demonstration in the studio with a model.

Here, Fong shows how Eye AF works with the α6300 during a photo shoot with an infant (not the easiest subject to track!). The Eye AF demo starts at 2:47.

 Sony Artisan Patrick Murphy-Racey put together an excellent tutorial showing how he sets up Eye AF when he's shooting with the Sony α6300 and α7R II. We had a post on this video a few weeks ago. In case you missed it, here's the video.