Olympus OM-D E-M5 Digital Camera Review

Dynamic Range

In testing the Olympus E-M5, we have to commend the company for making a great leap forward in their ability to rein in high ISO noise with this new 16-megapixel sensor. When we tested the Olympus E-P3 last year, we loved its physical design and small touches, but we thought the sensor was, to put it kindly, on the way out. The E-M5 is much improved, with far superior high ISO performance.

Even at the shared minimum ISO of 200, the OM-D E-M5 offers a full stop of dynamic range improvement over the E-P3, with just over 6 stops of range available above a high (10:1) signal-to-noise ratio threshold. Compare that to just 5.19 on the E-P3 and you already have a large performance gap. When you start turning up the ISO, though, the difference is even greater, extending as far as two stops at ISO 6400 and above. Despite this improvement, it's still pretty clear that the E-M5's Micro Four Thirds sensor falls a bit behind the best APS-C image sensors found in prosumer DSLRs and high-end mirrorless cameras like the Sony Alpha NEX-7.

We should mention that we test each cameras' JPEG engines, relying on the way they develop RAW shots right in the camera. This does mean that you'll be able to rescue a fair bit of detail from the images by shooting in RAW, processing on a computer, and tweaking settings to your liking. Still, we'd put the OM-D in the above average category for dynamic range, though it's far from the best. More on how we test dynamic range.