Olympus pulls out all the stops for its latest top-of-the-line Micro Four Thirds camera, the OM-D E-M1. Designed to woo Four Thirds-lens aficianados from its dSLRs -- this is the model that for all intents and purposes signs the death warrant on the E series -- the E-M1 incorporates a new antialiasing-filter-free 16-megapixel sensor, a hybrid phase-detection and contrast autofocus system, and fast continuous shooting in a cold-and-weather-sealed body. The result is a serious Micro Four Thirds camera that delivers some real advantages over dSLR alternatives, but not without some work before you use it for the first time.
The dual autofocus system, which the company dubs "Dual Fast AF," is an essential move for Olympus; Four Thirds lenses will, of course, work with Micro Four Thirds cameras, as long as you have a mount adapter, but Olympus' lenses are phase-detection optimized like most dSLR lenses. And Olympus, unlike its MFT buddy Panasonic, has a large base of Four Thirds lenses, with some very nice glass. To use them on the E-M1 you need to buy the $180 MMF-3 adapter, which is weather-sealed to match the body; the slightly cheaper $170 MMF-2 adapter will also work, just don't expect it to stand up to the elements.
In the E-P5, Olympus decreased the intensity of the antialiasing filter with good results. Here, the optical low-pass (OLPF) filter is gone entirely and it's correcting moire in-camera. The company also claims the camera's performing more intelligent sharpening, using the MTF data from the lens to determine the correct amount of sharpening to apply, plus it theoretically offers better chromatic aberration correction, via the TruePic VII version of its image-processing engine. (That's one TruePic more than the E-P5.)
Note: I think Olympus should be whacked upside the head for its image-processing defaults. In order to select the best quality JPEG, you have to first enable it in a custom menu, then select it in the image-quality settings; it defaults to Fine JPEG rather than Super Fine. If you don't read the manual carefully you would never know this setting existed. It's the same in the E-M5. Olympus says that the difference between Fine and Super Fine is negligible and that only a subset of people will benefit from using it, but nowhere are the use cases explained.
Overall the image quality out of the E-M1 is excellent; certainly better than the E-M5, as good or better than the E-P5 and really competitive with the D7100. The default Fine JPEGs look clean through ISO 800 and remain relatively usable through ISO 1600; shooting raw buys you at least another stop of detail over theses JPEGs, however, and even as low as ISO 100 you can get better results with raw than over the default JPEG settings. The color noise remains fairly fine-grained until about ISO 3200, which means that converting night shots to monochrome produces a nicer grain than you might otherwise see.
The color defaults to Natural, and JPEGs render with excellent, accurate color reproduction without looking flat. The dynamic range isn't exceptional -- it doesn't preserve much recoverable detail in clipped highlights or shadows -- but for relatively contrasty images you can pull back the highlight and shadows without much contouring or introduction of color noise.
|Click to download |
(note: all shot at Fine JPEG)
|ISO 200 ||ISO 800 ||ISO 3200 |
I was pleasantly surprised by the video quality. Normally, I find Olympus' video full of artifacts, but the E-M1's looks pretty well resolved, with no gratuitous moire (I did see some on high-frequency lines) or edge artifacts. There's also some wobbling on quick camera movements. It could use some grading -- right out of the camera it looks a bit flat, though not seriously washed out -- but otherwise it's quite nice. The audio sounds good, though there isn't much in the way of adjustments if you need more control. As with the E-P5, Windows 7 Media Player can't play Olympus' QuickTime movies, though oddly Windows 8's can.
In addition to testing with some my favorite MFT lenses, the 45mm f1.8, I was able to test the new 12-40mm f2.8 lens that Olympus might offer as part of a kit at some point but for now is only offering rebates for a simultaneous purchase. I really like the photo quality of the lens. It seems to have excellent light transmission and edge-to-edge sharpness, with a round aperture, and to me looks relatively sharp from f1.8 up through about f20.and
The E-M1 is fast, but not without one caveat. It powers on, focuses, and shoots in just under 0.8 second. Time to focus and shoot in either bright or dim conditions runs about 0.2 second, and time for two sequential nonburst shots, either raw or fine JPEG, also runs about 0.2 second. Adding flash to that bumps to a reasonable 1.7 seconds.
Enter the caveat. During performance testing, we test in shutter-priority with the shutter speed at 1/125 second and set the lens to its widest, usually resulting in the the aperture open to f4 or f3.5 in our bright condition test. At that aperture with the new 12-40mm f2.8 lens at 12mm, the E-M1's AF would not lock on the center of the scene, though it would pretend to do so and shoot anyway. After discovering this, I moved the focus point up one step to ensure focus lock. Interestingly, performance is the same regardless of whether it lcoks focus. I don't know whether it was a problem with the lens or the AF system -- I suspect it's a result of the wide angle, the widest we've tested with our current methodology and will keep it in mind in the future -- but moving the AF point seems like a reasonable solution.
Continuous-shooting speed also zips along nicely. In high-speed mode, which sets the focus, exposure, and white balance on the first frame it achieved its rated 10fps for at least 105 fine-quality JPEGs. (Normally I don't test that mode, but since I did it by accident I figured I'd report the results.) Switching to the low-speed burst setting of 6.5fps, It delivered that for both Fine JPEG and raw files; raw doesn't slow until at about 40 shots (using a 95MB/sec card), which is quite good.
On the imaging sensor, one out of every 16 pixels -- one out of every eight of the green pixels in the Bayer array, to be precise -- is replaced with a phase-detection sensor. The missing image value is then interpolated. Like the system in the Canon EOS 70D it's measuring directly off the focal plane, which helps drive the lens directly toward the correct focus point, the biggest problem when using phase-detection-optimized lenses with contrast-detection-based systems.