Image quality

Out-of-camera JPEG shot using the 'Natural' picture profile.
ISO 640 | 1/400 sec | F2.5 | Panasonic Leica 42.5mm F1.2
Photo: Chris Niccolls

The E-M1 III features the same 20MP sensor as its predecessor and image quality remains top notch among Micro Four Thirds cameras. The E-M1 III also benefits from the addition of the same high-resolution shooting modes (handheld and tripod), first introduced in the E-M1 X.

Key takeaways:

  • 20MP sensor outputs good Raws, on par with the best Four Thirds sensors
  • Lovely JPEG color rendering
  • JPEGs display intelligent noise reduction but sharpening is aggressive and a bit clumsy (at default settings)
  • 'High Res Shot' modes offer both a resolution and a noise benefit
  • Neither tripod nor hand-held 'High Res Shot' modes handle motion particularly well, though results from the former look a little more natural

Studio scene

Raw

Raw detail capture from the E-M1 III is very good and similar to other 20MP Four Thirds cameras. Detail capture also isn't too far behind its APS-C rivals, though they're capturing a wider image. The E-M1 III also captures similar levels of false color to other Bayer sensor cameras here, but the Fujifilm X-T4's X-Trans color array does away with these artifacts, for the most part.

At higher ISOs noise performance is similar, or ever-so-slightly better than the G9, but noticeably behind the APS-C gang, especially the X-T4 (again). And by ISO 12,800, you've likely cranked this Four Thirds chip beyond usable territory.

JPEG

In JPEG mode the E-M1 III shows off those wonderful Olympus colors we've come to know and love (shot using the default 'Natural' profile'). Reds are well saturated, yellows look spot on (not too green), and greens and blues both look nice and punchy, which should translate to nicely-rendered trees and skies.

The E-M1 III appears to be using large radius sharpening (similar to the E-M5 III), noticeable in the 'haloing' around the outer edge of the grey square. While this kind of sharpening looks good in some instances, in others it can be clumsy with fine detail.

At higher ISOs the Olympus, Panasonic, Fujifilm and Nikon all do similarly good jobs not blurring away the detail in the fake grass. However Sony's a6600, which uses context-sensitive noise reduction, bests them all.

High-resolution mode

The E-M1 III offers a tripod high-res mode that can produce 80MP Raw files by using its image stabilization to shift the sensor 8 times in 0.5 pixel increments. The result is a huge gain in resolution. And downscaling high-res shots produces impressive results. But that's not all: High-res mode also gives a noticeable noise benefit. When downsized you can see the difference is at least two stops. Just be aware, tripod high-res mode is best suited for scenes with little movement.

Dynamic range

Dynamic range from the E-M1 III's 20MP sensor is very good, and on-par with the best performing Four Thirds chips we've seen. Our ISO invariance test shows that the sensor is adding very little noise to its images; this opens up the option to use around 3EV lower ISO in low light situations and brighten the image in post with very little additional noise added by the camera. This can be useful for situations in which you want to preserve highlights, since you won't amplify them to clipping.

In situations with very bright light, where lowering the ISO isn't an option for preserving highlights, shortening the shutter speed or stopping down the lens is. But it's worth keeping in mind that reducing the exposure means fewer photons being recorded by the sensor, resulting in noisier-looking images due to shot noise. You can see the results of this phenomenon in our exposure latitude test. Comparing the E-M1 III back to the 16MP sensor in the E-M5 II, you can see that they both get noisier as you reduce exposure (to capture more highlights), but the E-M1 III is slightly less noisy: a difference that comes down to its slightly cleaner sensor performance.

It's situations like this where larger sensor cameras have a clear advantage over Micro Four Thirds, since they capture more total light at the same exposure values. However if you switch over to high-res mode, that advantage evaporates before our very eyes, because merging the additional shots cancels-out the two-stop difference we'd otherwise expect.

High-res mode: tripod vs hand-held in the real world

Tripod 'High Res Shot' mode (80MP)

Hand-held 'High Res Shot' mode (50MP)

There are two 'High Res Shot' modes offered in the E-M1 III – a tripod-based version that can produce up to 80MP images and a handheld version that produces 50MP images. You can view examples of each above (click to open in a new window for 100% views).

Neither function is particularly well-suited for handling motion as you can see from how each renders the moving cars and boats in the scene. In the tripod version there doesn't seem to be any form of motion correction, so the moving cars and boats just look like long exposure trails, the result of 8 consecutive frames being combined. At 100%, there are some artifacts, but the movement actually looks pretty natural when viewed at a reasonable magnification. However, for scenes with more random movement (i.e. not so directional), we'd anticipate stranger results.

The hand-held version instead seems to be trying to correct the motion and isolating a single frame of each moving vehicle, to include in the final image. It works ok for the boats, but the cars just look, well, odd. We'd avoid using this mode for anything with serious movement.

Motion aside, both high-res options produce impressive levels of detail. However the tripod mode not only produces a higher-res file, the output is also a bit sharper thanks to precise sensor shifts that cancels out the Bayer filter array.