Autofocus and performance

Processed in Adobe Camera Raw 12.
ISO 125 | 1/2000 sec | F5.6
Photo by Dan Bracaglia

The E-M5 III has essentially the same autofocus system as the larger E-M1 Mark II and E-M1X models, though it lacks the latter's subject-specific 'deep learning' autofocus modes. This means it can be a capable action and sports camera, but autofocus tracking is lackluster compared to the best of its competition and some ergonomic quirks keep the E-M5 III from being as good as it could be.

Key takeaways:

  • Acceptable autofocus performance if you keep your AF area or zone over your subject
  • Autofocus tracking lags behind the competition, but increasing C-AF sensitivity and using the electronic shutter will boost your hit rate
  • Fn lever allows for quick changing between AF modes and areas, but does not remember face / eye detection or focus limiter settings
  • Overall performance and responsiveness is impressive

In depth

The E-M5 III comes with the same autofocus system as the E-M1 Mark II, so it has a phase-detection system where AF points spread across the frame, and 121 selectable areas for the user to choose from. There are also multiple zones of AF areas, as well as a tracking function that attempts to lock on to a subject (or portion of a subject) and follow it around the frame for you. There's also a customizable autofocus limiter (we found it handy for photographing birds), as well as face and eye detection.

There's also a provision for adjusting the C-AF sensitivity; the default value is '0', and you can adjust it up to +2 or down to -2. The in-camera tips aren't much help, telling you to simply 'adjust the sensitivity depending on the movement of your subject for still photography.' The user manual says this setting 'sets the tracking sensitivity for C-AF.' None of this is terribly helpful, but Olympus did tell us back when we reviewed the E-M1X that users should boost the sensitivity for increasingly speedy and erratic subjects.

Fn lever

The rear Fn lever can be used for a number of functions; it can change the behavior of the command dials, act as a power switch, or swap between focus modes (MF, S-AF, C-AF) and areas (single area, zone, etc), which is how it's set up by default. This has the potential to be really powerful, but falls short in practice.

The Function lever surrounds the AEL/AFL button on the rear of the E-M5 III and can be used to change the function of the dials, autofocus settings, or even act as an on/off switch.

For example, I kept the camera set up so that one Fn lever position was S-AF and a single area, which gave me reliable precision for static subjects and general shooting. Flipping the switch entered 'C-AF + Tracking,' so I could easily track and keep moving subjects in focus. But if I want one of those Fn lever positions to, say, be set up for photographing people using Face and Eye detect, well, I can't. The Fn lever doesn't save that preference, so I have to go into the Super Control Panel or main menus to enable or disable face detection modes. The same goes for the custom AF limiter, which also requires a dive into the main menus to adjust or engage.

There's no denying that, despite our qualms with its autofocus, the E-M5 Mark III is capable of getting fantastic results.
ISO 200 | 1/2000 sec | F4.5
Photo by Richard Butler

We reached out to Olympus with this information, and while they cannot comment on future firmware update plans, they did say that user feedback will be considered as they make decisions related to lever function improvements.

Continuous autofocus performance

We found the continuous autofocus of the E-M5 III to be a bit disappointing for a camera with these specifications at this price. To test continuous AF performance, we first try to shoot a subject approaching at a steady speed using a central AF point. This lets us see how good the camera is at assessing subject distance and whether it can drive its lens to that point quickly. Unless otherwise noted, we kept the E-M5 III's C-AF sensitivity at its default setting of '0'.

On the E-M5 III, we tested both the mechanical shutter, which tops out at 6fps, and the electronic shutter, which tops out at 10fps. Here's how it did.

Mechanical shutter (6fps)
Electronic shutter (10fps)

As you can see, the E-M5 III turns in a decent performance, but it just isn't up to par with what the competition is capable of these days. We did find, though, that the electronic shutter gave us a few more keepers, and since it also boosts the maximum burst rate, we'd recommend using it when possible.

Now that we've seen how the straight-on performance looks, we'll have the subject weave across the camera's AF region in a way the camera can't predict. This has the advantage that the approach rate varies as the subject changes direction. For this test we use the camera's C-AF + Tracking mode, so it needs to identify and follow a subject around the scene, as well as trying to keep it in focus.

Mechanical shutter (6fps)
Electronic shutter (10fps)

Oh, dear. Whether using the mechanical or electronic shutters, the E-M5 III struggled mightily, turning in 40-45% of its total images out-of-focus. Most often, the camera would lose the cyclist as he rounded a turn, and would sometimes get him back when he crossed through the middle of the frame, but then lose him again at the next turn. This could be due to the subjects rate of acceleration relative to the camera. Again, this is with C-AF Sensitivity set to its default of '0'. We then boosted it to '+2' to see if anything changed.

Electronic shutter, C-AF sensitivity +2

At this setting, we saw our in-focus hit rate increase from around 60% to around 80%. The E-M5 III still lost track of the cyclist around the first corner (shown here at the beginning), but then regained focus and maintained it fairly well through the end of the run. That's a pretty good boost from one changed setting.

An increase in hit-rate from ~60% to ~80% is a good boost from one changed setting

So for best results with autofocus tracking on the E-M5 III, we find it's best to use the electronic shutter and set the tracking sensitivity to +2. With around an 80% hit rate, it's not too bad a showing, but it's not great against the competition at this price.

Face and eye detection

Face and eye detection on the E-M5 III works pretty well for casual use. Unfortunately, if there are multiple faces in a scene, the E-M5 III doesn't allow you to choose which one to focus on: it picks for you. You also only get a brief indicator of which face the camera has chosen. The camera will outline the chosen face with a green box upon half-pressing the shutter, but then the green box disappears, and every face present will have a white box surrounding it. If you tap the screen to place focus, it simply gives you a green rectangle in that area, disabling face and eye detection.

Face detection looks and works a little differently in the C-AF + Tracking mode, with the green 'subject' box growing and shrinking with the size of the face in the frame. Unfortunately, as with other AF areas, you don't get to choose which face to focus on by moving the AF area over your subject - it just chooses for you. In this mode, though, you can tap on the screen to choose a subject's face, which will then be tracked around the screen.

Overall performance

In every respect, the E-M5 III is a highly responsive camera. It reacts instantly to your inputs, whether that involves changing exposure settings or diving into the menus. Boot-up times are swift, and while there's a slight delay when switching from the rear screen to the optical viewfinder, it's not hugely bothersome.

The E-M5 III can take advantage of UHS-II cards for speedier transfers.

The E-M5 II also comes with a UHS-II card slot for its SD memory cards, so write times are fast and you're rarely waiting for the buffer to clear.