Body & Design
The E-M1 has a burlier appearance than the E-M5, gaining a more substantial hand grip and a profusion of buttons and direct controls. There's a button to access just about every imaginable feature, and of course, since it's an Olympus, it's also possible to re-configure many of these. The body is dust, splash, and freezeproof (to -10 °C/ 14 °F), although you'll need to use a similarly-sealed lens to benefit from this.
The E-M1's more pronounced hand grip allows the front and rear control dials to be better spaced-out (an occasional criticism of the smaller model), and the buttons are all larger and more positive than the E-M5's. The result is a camera that sits even more comfortably in the hand, especially if you have larger hands, and is easier to operate. The magnesium alloy construction means it's still pretty light, though.
Ultimately, despite its authentically semi-pro appearance, the E-M1 is still a pretty small camera compared to DSLRs, especially in terms of body thickness. The disadvantage the previous top-end E-series cameras had was that they ended up being as big as any other DSLR (the E-3 and E-5 were essentially the same size as full-frame DSLRs, at which point it became hard not to measure them up against those cameras). The E-M1 may be large for a Micro Four Thirds camera, but it's not big in the grand scheme of things. Its lenses tend to be smaller, too.
Top of camera
It would be hard for the top of the E-M1 to feature more controls, or look more OM-esque - the On/Off switch on the left shoulder and the new button turret next to it are reminiscent of the original OMs' film winding handles and Auto/Manual switches. From here you get direct access to focus, metering and drive modes, along with one of the E-M1's new features - in-camera generation of high dynamic range composite images. The camera has a unique trick here - it automatically previews how the HDR image should turn out in the EVF, by pulling up the shadows and re-balancing the local contrast.
The positioning of the power switch divides opinion in the DPReview offices - some of us think it's just fine, others dislike it. Most cameras these days place this control close to the shutter button, allowing quick operation by your index finger without having to change your grip. The E-M1, in contrast, requires you to shift either your left hand from under the lens or your right hand off the grip, which could cause you to miss a shot. It's a relatively minor point, but one worth pointing out.
On the right-hand side, the camera's mode dial has gained a sprung, toggle lock. It's a nice implementation; if you like your mode dial locked, you simply lock it after making a change, but if you don't, you can leave it unlocked. Beyond this, the right shoulder is dominated by the two control dials, with the Fn2 and REC buttons nestling between them and Fn1 sitting on the angled shoulder of the camera.
Tilting capacitive touchscreen
The E-M1 uses the same screen as the E-P5 - a 3:2, 1.04m dot LCD panel that gives a slightly-wider-than-VGA 720x480-pixel display. The 3" capacitive screen tilts 80° upwards and 50° downwards, and a ridge down the left side makes it relatively easy to pull out and adjust. Like all tilt-only screens, though, it adds nothing when shooting stills in portrait format.
One really welcome change compared to the E-M5 is that the moment you tilt the screen, the EVF's proximity sensor is disabled. This means that the camera will no longer switch over to the EVF if you move it too close to your body, which counts as a big improvement for waist-level shooting.
The E-M1 uses the same, 2.36M-dot high-res LCD that we saw in the VF-4 accessory finder for the E-P5, and it's very good indeed (it's apparently the Epson panel we've also seen in Fujifilm's X100S). As with the VF-4, it's large and detailed, with a smooth refresh rate that only slows down in pretty low light. It offers essentially the same size view as the optical viewfinder of a full frame SLR, which is impressive in such a small body. This means it's also usefully larger than the E-5's viewfinder.
The E-M1 gains an feature called 'EVF Auto Luminance' which brightens and darkens the backlight of the EVF in response to the brightness of the scene. The effect is clearly visible, particularly in low light; the E-M1's EVF becomes visibly less bright than the E-M5's when compared side-by-side, for example, and a closer match to the ambient brightness. Olympus believes this helps make the experience of using the finder more comfortable and OVF-like, as your eye doesn't have to adjust to a brighter finder. Since only around one user in 50 will find out how to disengage it, you may find you're getting its benefits it without realizing.
Viewfinder size and view
One figure hidden away in the specs is the size of the viewfinder (often in a format that makes comparison between competing types impossible). The size of the viewfinder is a key factor in a camera's usability - the bigger it is, the easier it is to frame and focus your shots, and the more enjoyable and involving a process it is.
Because of the way viewfinders are measured (using a fixed lens, rather than a lens of equivalent magnification), you also need to take the sensor size into account, so the numbers in the diagram below are the manufacturer's specified magnifications divided by the respective 'crop factors'.
|The E-M1's is one of the largest electronic viewfinders around: its 0.74x equivalent magnification places it close to the very best optical finders found in full frame SLRs such as the Canon EOS-1D X. It also offers 100% coverage of the field of view, allowing critically accurate composition.|