Olympus OM-D E-M1 Digital Camera Review
The new OM-D is a bold bet for Olympus.
By the Numbers
It’s been a big year for Micro Four Thirds cameras. The Panasonic GX7 tore through our labs just a few weeks ago on its way to the best overall score we’ve seen this year. The Olympus OM-D E-M1 is here to challenge the throne already, building on the incredible success of Olympus OM-D E-M5 with a new 16.3-megapixel CMOS image sensor, processor, and a host of performance upgrades. With solid dynamic range, great resolution capabilities, 10fps shot-to-shot burst shooting, and excellent JPEG and RAW output, the E-M1 has done enough to put it alongside the Panasonic GH3 as the best mirrorless camera we’ve reviewed to date.
Editor’s Note: As the Olympus OM-D E-M1 is still relatively new, standard RAW profiles are not yet available. We’re currently relying on results derived using Adobe Lightroom 5.2’s preliminary support for E-M1 RAW files. When the support becomes final we will revisit these results and make changes as necessary.
As with other Olympus cameras, the JPEG output of the OM-D E-M1 is generally tuned for vibrancy and enhanced contrast, not clinical accuracy. The one exception to this is the E-M1’s Muted mode, which offers very good color accuracy (∆C00 of 2.35) and near-perfect (100.5%) saturation. This isn’t quite as good as the Nikon D4 or Canon 1D X, though anything below 2.3 is generally considered excellent.
The other modes are far less accurate, though that’s not their aim. The Portrait and Natural modes are still fairly accurate, with a ∆C00 of roughly 2.92 with roughly 104% saturation. If you’re looking for something with a little more punch, opt for the Vivid (∆C00 3.3, 117.9% saturation) or iEnhance (∆C00 3.15, 127% saturation) modes.
One of the major drawbacks of smaller sensors—especially early Micro Four Thirds sensors—is the generally low signal to noise ratio. The OM-D E-M5 represented a quantum leap forward for Olympus’ sensors, and we’re happy to report the E-M1 continues that trend.
While the RAW performance will best be addressed below when we talk about dynamic range, we also are able to check out how the camera's noise reduction profiles are applied. The E-M1 offers four levels of noise reduction—Off, Low, Standard, and High—with the “off” setting still showing some evidence of noise control.
At the base ISO of 100, the Off setting returned a noise percentage of just 0.57% for JPEG images. That rises to 0.74% at ISO 200, 1.03% at ISO 800, 1.43% at ISO 3200. The E-M1 bumps up against the 2% threshold (where quality really takes a hit) at ISO 6400, hitting 2.49% at ISO 12800, and 2.93% at ISO 25600.
As you can see in the 100% still life crops above, you can pretty safely shoot up through ISO 6400 and get usable results from JPEGs. That’s where noise begins to cross 2% and image quality takes a noticeable hit. If you are applying noise reduction (or shooting in RAW and developing yourself) you can even go higher than that, with Low hitting 2.04% at ISO 12800, Standard hitting 1.98% at ISO 25600, and High topping out at 1.56% at ISO 25600. The only caveat that applies there is the increasing levels of noise reduction will result in fine detail being smudged away, especially at those high ISO speeds.
Before you buy the Olympus OM-D E-M1, take a look at these other interchangeable lens cameras.
The Olympus OM-D E-M1’s small sensor isn’t able to stand up against the full-frame competition in our dynamic range test, thought it does outperform the Panasonic GX7 at high ISO speeds. Looking strictly at luminance values, we were able to get around 10.5 stops of dynamic range from the E-M1 at the base of ISO 200. Depending on how you tune the RAWs you can probably squeeze another stop out of the footage, but it still lags slightly behind the 12-13 stops you’ll get from a full-frame camera.
If you want to look at dynamic range from a more technical perspective, you would look for the point at which the signal-to-noise ratio falls to below 1:1—where you can no longer reliably differentiate between what is signal and what is noise. Since noise is so destructive to photographic quality, we take that a step further and look to the point where signal-to-noise ratio falls below 10:1.
For the E-M1, we found that at the base ISO of 200 there are 7.71 stops of this “high” dynamic range. This is almost identical to the GX7, the most recent Micro Four Thirds camera we’ve reviewed. From there the E-M1’s performance falls to 6.19 stops at ISO 400, 5.08 stops at ISO 800, and 3.58 at ISO 1600. There are 2.65 stops of range at ISO 3200, 1.96 stops at ISO 6400, and ISO 12800 and 25600 produce no stops that meet that criteria.
The GX7 hangs with the E-M1 through ISO 800, but it falls off dramatically from there. If you need to shoot at high ISO speeds frequently and want the best Micro Four Thirds sensor available, the E-M1 is the way to go.
The Olympus E-M1 performed very well in our resolution tests, largely thanks to its 12-40mm f/2.8 Pro lens. While the lens is one of the most impressively built Micro Four Thirds lenses to date, it’s also tack sharp.
In our testing we found that the lens was extremely sharp in the center at max aperture and full wide angle, good for around 2300 line widths per picture height in the center at MTF50 and around 1950 LW/PH near the edges with some slight astigmatism. At longer focal lengths the center resolution drops slightly to around 1750 LW/PH, though that may also be the way that the camera processes JPEGs. Stopping down to f/5.6 produced slightly improved corner resolution at all focal lengths, with the center remaining very sharp.
One of the major benefits of this lens over other Micro Four Thirds zoom lenses is the fixed maximum aperture. While the signal-to-noise ratio issues of the Micro Four Thirds format have been mitigated greatly in both the GX7 and the E-M1, one major issue is the diffraction limit of shooting with smaller sensors.
As with other Micro Four Thirds lenses, resolution begins to fall off as early as f/8 with the E-M1 and its new lens. The ability to maintain a large f/2.8 aperture throughout the focal range gives you lots of flexibility to preserve as much resolution as possible, even when you need to zoom in on your subject.
The Olympus OM-D E-M5 wasn’t overly renowned for its burst shooting, but the E-M1 very well may be. In our testing the E-M1 was able to capture exactly 10 frames per second when shooting continuously, even when shooting RAW+JPEG with image stabilization and continuous autofocus activated.
We were also impressed with the E-M1’s continuous shooting capacity, as it was able to capture 34 RAW shots, 43 JPEGs, or 29 RAW+JPEG images in a single burst when using a class 10 SDHC card. This is slightly less than the 50 RAW shots that Olympus claims, but you may be able to get more mileage if you use a different card or under different conditions.
Like past Olympus M43 cameras, the OM-D E-M1 is not well equipped for video shooting. Even though the E-M1 is the first M43 offering from Olympus to feature a real microphone jack, nothing has been done under the hood to improve the weak software at work. Offering up a shockingly mediocre 1080/30p shooting mode just doesn't cut it these days.
In bright light, we measured a sharpness of 615 lw/ph horizontal and 690 lw/ph vertical. When we dimmed the lights in our lab, we registered less detail—575 lw/ph horizontal and 650 lw/ph vertical.
In our minimum illumination test, we found that the E-M1 required 5 lux in order to create a picture of 50 IRE, a broadcast benchmark for image brightness.