Like other Micro Four-Thirds cameras, the E-M1's sensor has a resolution of 16 megapixels: small enough to keep a lid on noise, large enough for oversized prints. By eliminating the optical low-pass (anti-aliasing) filter, the E-M1's sensor should, in theory, generate images with finer detail. I can't tell if it's the lack of the anti-aliasing or the excellence of the lenses I've tested it with, but the E-M1 can deliver tack sharp shots.
The ISO dial goes up to 25,600. As with every other camera ever made, noise increases with ISO. But between particularly between ISO 200 and 3200, with proper exposure, the E-M1 will deliver images that are as good as those from any APS-C camera today and that often rival images from full-frame cameras.
The E-M1 is helped enormously by best in-body image stabilization (IBIS) around. Olympus's five-axis sensor shift IS technology adjusts not just for up-down or side-to-side camera shake but for rotation on three other axes, and it's very effective. IBIS helps every lens you use on the camera and on a mirrorless camera like the E-M1, IBIS stabilizes the image while you're composing the shot.
The E-M1's Dual FAST autofocus system combines on-chip phase detection autofocus with contrast detect autofocus for responsive, accurate autofocus. You can target focus on 81 (9-by-9) points, available almost anywhere in the frame. Touching one of the buttons on the four-way controller instantly moves the focus target, something I found disconcerting at first, but now regard as brilliant. On the other hand, when I'm shooting with the camera on a tripod, I find myself increasingly using the touch-screen to focus on the rear monitor. While I'm talking about autofocus, I have to mention the E-M1's remarkable eye-priority face detection. I've not had good luck with face detection autofocus in the past, but the E-M1's system is scary good.
I still use manual focus fairly often, and high-tech innovations like focus magnification and focus peaking make old-school focusing easy and reliable. You can configure the camera to magnify the image automatically when you turn the focus ring of the lens, but I find that intrusive, so I invoke magnification by tapping a button on the front of the camera under the lens mount, which is within easy reach of the ring finger on my right hand.
The E-M1's video mode supports 30p only. By contrast, Panasonic's best micro four thirds cameras serve up the whole can of p's: 24p, 25p, 30p, 50p and 60p. Advantage: Panasonic.
Nevertheless, even in regard to video, the E-M1 improves on earlier Olympus cameras. You can plug an external mic into the E-M1 and with a little trial and error (no graph for levels) adjust input levels. And the E-M1 has one or two proper strengths worth mentioning. The E-M1's stunningly effective in-body stabilization isn't just for stills: it also makes it possible to shoot steady video without a tripod.
Sign up for CIO Asia eNewsletters.