The (Almost) Perfect Autofocus of the Sony a7R III: a Hands-On Review

By: Anabel DFlux

Focus is one of the most important concepts for a photographer. It can make or break an image. Whether you’re a pixel peeper like me who always looks for technical critical focus or an image maker who uses specific focus points to tell a story,  how the camera focuses is everything.

#SonyAlpha #AutomaticAF #AF

That’s why the newest addition to the Sony Alpha series is so conversation-worthy. With the 399 focus points on the Sony a7R III, and its ability to track focus like no other, the company touts it’s hard to get a shot that’s out of focus. This camera is like an artificially intelligent robot – it can predict and figure out exactly what you want in focus on.
With the thumb joystick on the back of the camera, you can quickly and easily change your focus point. And its AI Servo is out of this world. It could figure out the entire outline of a subject and hold on to it for dear life.
I take varying images – shooting animal action sports, live concerts, and everything in between. So I took all the boasting I’ve heard about this camera and put it to the ultimate test.

About the Sony a7R III

The a7R III is one of Sony’s newest and flashiest addition to its impressive mirrorless line of cameras. According to its website, the Sony a7R III sports the following drool-worthy perks:

• 42.4 MP 35mm full-frame Exmor R™ CMOS and enhanced processing system
• Standard ISO 100-32000 range (upper limit expandable to 1024005, with a lower limit of 50)
• Fast Hybrid AF with 399-point focal-plane phase-detection AF and 425-point contrast-detection AF. The focus modes include:
  • AF-A (Automatic AF)
  • AF-S (Single-shot AF)
  • AF-C ( Continuous AF)
  • DMF (Direct Manual Focus)
  • Manual Focus
• Face detection, with Modes:
  • Face Priority in AF (On/Off)
  • Face Priority in Multi Metering (On/Off)
  • Regist. Faces Priority (On/Off)
  • Face registration (max. number detectable: 8)
• High-speed continuous shooting of up to 10fps (12fps with AF/AE tracking)
• 5-axis image stabilization with 5.5-stop exposure advantage
• 4K video recording
• Dual card slots with simultaneous or consecutive recording
• Silent Shooting Mode

The camera is compatible solely with Sony E-mount lenses, including G-Master and Zeiss lenses (sought after in the Sony world). The aspect ratio is 3:2, and the camera can record still images in JPEG, (DCF Ver. 2.0, Exif Ver.2.31, MPF Baseline compliant) and RAW (Sony ARW 2.3 format). The images are quite large: a 35mm full-frame image is 42MP (7,952 x 5,304 pixels), which in uncompressed RAW format takes up about 80MB of storage.
The camera also has built-in noise reduction software you can turn on or off as needed.
But what really set this camera apart (and why I fell in love with it) is the autofocus.

The Sony a7R III Autofocus Features

The a7R III allows for silent shooting at up to 10fps with AF/AE tracking – great for those who do wildlife photography. Shooting at 10 FPS yields up to 76 images at a time (when shooting JPEG).
Its phase-detect points cover around 47% of the sensor area. When you combine that with the contrast-detect sensor areas, the total AF coverage is nearly 68% of the frame.

Advanced algorithms provide high AF precision down to light levels as low as -3 EV for more reliable autofocus in dark scenes. The enhanced Fast Hybrid AF speeds up AF approximately two times faster under dim lighting conditions. The camera’s infrared technology allows it to autofocus even in extremely low or difficult lighting situations.

The camera also has an ‘eye autofocus’ setting. You read that right: it can find eyes on your subject and lock focus on them with the push of a button. This is photographic witchcraft and I love it. The a7R III’s Eye AF evolves with twice the effective eye detection and tracking, even when shooting a moving portrait subject. It’s touted by the company to work when:

• the subject’s face is partially hidden
• the subject is looking down or wearing glasses
• the subject is backlit
• the lighting is dim or low
• the subject is far away.

The a7R III includes a touchscreen that provides touch AF, focus point dragging and focus racking features. The AF-C (continuous autofocus) option feature is extraordinary. The camera can keep tracking the subject even if it’s changing direction erratically or an object gets in the way.

Tip: The ‘Expand Flexible Spot’ mode is a good one to start from, and works well with the AF joystick for quick adjustments to the preferred focus area.

Real Life Use

This camera is fast and accurate. With my DSLRs, I usually have to refocus multiple times. But I didn’t have to do it once on the Sony a7R III. I think mirrorless cameras really outshine most DSLRs in the autofocus department.
Here’s how it did in various scenarios:

Action and Sports

I photograph a lot of action, and when I first bought this camera I took it to a Frisbee dog competition to test it out. I was absolutely blown away by the autofocus. The camera even recognized a dog’s face with its facial tracking autofocus and maintained focus on the dog’s face throughout its trick-induced performance. When the dog moved further away the focus changed to the animal’s entire body, which I appreciated.
Regardless of how spontaneously the dog moved, the focus remained locked.

I typically use my Canon 7D Mark II for animal sports photography due to its speed and the fact the body is intended for action. But I now prefer the a7R III due to its superb tracking. The 7D tends to get lost when there isn’t much contrast between the subject and the other objects in the frame, such as photographing in the fog. (Many of these dog sporting events happen around 7am when the fog rolls onto the field.)
The Sony mirrorless clearly identified the subject despite the lack of contrast. It can even refocus on dogs running at me without needing any prompting or additional technique.

Portraits

Portraits are an absolute breeze with this camera. From face tracking to eye tracking, it’s almost impossible to take an out-of-focus image unless you have your settings wrong. As I mentioned earlier, the eye tracking feature is said to work in problematic scenarios (the face is partially hidden, the subject is looking down, etc.)
Well, I can confirm that what Sony promises is true. It works in all of those scenarios. Even when I shot a model wearing unnatural contacts and bright glittery makeup, the camera had no issue.

Dimly-Lit and Golden Hour Portraits

Much like the camera’s success with well-lit portraits, the Sony a7R III can focus on portraits in dim light as if they were lit to perfection. I’m happy to say there was absolutely no difference between the two. Night portraits were a breeze.
The golden hour portraits were just as easy (not to mention exquisite). My other cameras have focusing issues when the sun is low and hitting the lens at an angle. But the a7R III breezed through and held focus on the subject no matter how the sun was hitting the lens glass.

Live Concerts

Dogs may wake me up in the mornings, but it’s the rock stars who keep me awake at night. In the evenings you’ll probably find me shooting a live concert with an arsenal of camera equipment to get me through the job.

Live concerts are extremely difficult focusing situations. In fact, they’re like a low-light sports situation. For the most part, you’ll have limited lighting, and have to deal with colored bulbs that can paint the subject with a very saturated color (such as the dreaded red hue).
Live concerts are also high-energy and filled with action as the guitarists swing their guitars and the drummer pounds away. You may not always have enough contrast to work with, and plenty of annoying obstacles to get in the way of whatever musicians you’re photographing.

Much like I found success in dog sports photography, the Sony a7R III does mighty well at maintaining focus on the subject despite erratic movement or instruments getting in the way. If the light is low but even, the camera does a splendid job of finding the subject thanks to its Advanced AF algorithms.

Unfortunately, live concerts are also where we hit a bit of a snag. As venue goers know, most music venues (especially small indie ones) don’t have consistent lighting on the stage. It can be uneven, sporadic, and wild. Some genres of music (e.g. metal and rock) really love using strobe lights on the stage as well.
And this is where the Sony a7R III flops terribly.
The moment strobes are used, the camera completely loses its ability to focus or find the subject. It’s a negative I haven’t seen covered in other reviews and one that keeps me from bringing this camera to a live concert (after having a particularly bad experience at a recent show).
When strobes were involved, none of the autofocus settings or adjustments worked. The camera began to hunt and then failed to focus at all. This happened with other native and non-native lenses. My guess is the infrared technology is affected by the strobing effects, but that’s just an assumption.

Non-Native Lens with an Adapter

As an avid 16-year Canon user with an army of L lenses, I have no plans on switching brands anytime soon. When I added the Sony a7R III to my kit, I immediately looked for ways to adapt my L glass to the Sony camera. (That way I’d need to buy only buy one native lens for the Sony and use the rest of my existing kit.)
After testing out several adapters I found that the Metabones Smart Adapter worked best.
Now it was time to test the autofocus on a non-native lens.

Although some of the autofocus features (e.g. eye-tracking) are disabled on non-native lenses, the facial recognition and AF-C (continuous autofocus) features worked like a charm. Once I’d calibrated the adapter to my lenses I didn’t experience any lag, searching or loss of focus. And despite certain features being unavailable, the camera was just as fast with non-native lenses as it was with native ones – even in low light. (I took this set up out for a spin during a club event.)
But the strobing issue was still there, which is why I’m convinced it’s a camera issue rather than a lens issue.

Final Thoughts

I have no regrets investing top dollar in this mirrorless camera. I find myself using it as much as my DSLRs, and I have three of them. I’ll often pick the mirrorless for more complex shoots simply because of its exquisite face tracking with autofocus.
Have I got you salivating? Think the Sony a7R III might be your next camera?

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