DxOMark just published their score for the Olympus OM-D E-M1 Mark II, the latest flagship mirrorless digital camera from Olympus. The Mark II version of the E-M1 is built around and entirely new imaging pipeline with a new 20 megapixels High-Speed CMOS sensor and TruePic VIII processor which together can deliver 60 FPS continuous drive and 4K video at 24 FPS. This speed is an entirely new level for a Micro Four-Thirds camera as is the launch price of $2000 USD.
The Olympus OM-D E-M1 Mark II achieved a DxOMark score of 80, the highest of any Micro Four-Thirds digital camera by a significant margin, surpassing the excellent Panasonic Lumix DMC-GX8 reviewed here which scores an impressive 75. Breaking down the E-M1 Mark II score into its 3 components gives it 23.7 color bit-depth, 12.8 EV dynamic-range and a whopping 1312 Sports points which related to High-ISO performance. The previous champion scored 23.5 color bit-depth,, 12.6 EV dynamic-range and 806 Sports points. This means that the leap in performance is mostly due to vastly improved image-noise.
Sensor-size is still a big deal when it comes to image-quality. Physics say this should be so yet Olympus is managing to close the gap with its latest technological advancements. As a comparison, the Olympus OM-D E-M1 Mark II gets the same overall score of 80 as the Pentax K-3 reviewed here (as was as the current Pentax flagship, the K-3 II which uses the same sensor) and the Canon EOS 1Ds Mark III. The K-3 was launched in 2013, while the 1Ds Mark III in 2007, meaning there is about a 4 year gap between Micro Four-Thirds and APS-C, while a 10 year gap between Micro Four-Thirds and Full-Frame.
Bit-depth is not that big a deal. Most cameras score rather closely with APS-C bit-depth being 24.8, just slightly over 1-bit per pixel more than the E-M1 Mark II. The best Full-Frame gets 26 bits, a little more than 1-bit extra. Medium Format leads this core with a respectable 26.5 bits-per-pixel.
Dynamic-range is much more critical to photography. Here, the best APS-C camera scores 14.1 EVs, while the best Full-Frame 14.8, compared to 12.8 EV for the latest Olympus mirrorless flagship. Recall that a one stop difference means twice the brightness can be captured in highlights. This is where sensor-size dominates the most. As such, Micro Four-Thirds cameras, even those launched over 3 years ago like the Panasonic Lumix DMC-GX7, do not score much less, 12.2 for the GX7 for example.
Low-light performance is also dominated by sensor-size, yet in this case can be minimized by sensor-design. The highest scoring APS-C camera scores 1438 which is less than half of what the best Full-Frame camera can deliver, which is 3702. Surprisingly, the Olympus OM-D E-M1 Mark II scores a 1312 which is remarkably close to the best current APS-C score. This could mean that APS-C sensors are due for a refresh or that Olympus is managing to reach minimal noise from circuitry, leaving only Photon noise which is simply always there.
Did Micro Four-Thirds bring down the gap in terms of low-light performance as much as is physically possible? Only time well tell but, with the Olympus OM-D E-M1 Mark II, there seems to be little reason to carry-on the bulk of an APS-C camera and its compatible lenses!