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.
If you're a budding Roger Deakins or Gordon Willis, well, you have probably already placed your order for a Panasonic DMC-GH4. If, like me, you're mainly a still photographer, the E-M1's more limited video options, combined with its excellent IBIS, may be advantages. My favorite feature: you can take a still photo while shooting video.
Glass half full' features
Like every camera, the E-M1 is a bundle of compromises, and no camera can possibly meet the needs of every photographer. But for many photographers, the E-M1's compromises will seem reasonable, even if you are aware of what you're missing.
The E-M1 has built-in Wi-Fi that lets you communicate directly with a well designed free app on your iPhone or iPad called Olymus Image Share. In addition to serving as a great remote control system for the camera, Image Share can download pictures from the camera to your phone as well as geotag them. This ad hoc Wi-Fi system won't let you copy pictures to a laptop. And geotagging on the phone isn't as easy as having GPS built into the camera. But I've found it useful, while shooting in the field far from a normal W-Fi router, to be able to move a picture to my phone, geotag it, give it a quick edit in Snapseed, then use my iPhone's cellular connection to mail it to a client.
It's a shame that the E-M1's touch screen can't be used to navigate its rather extensive system of menus or change very many settings on the monitor. Nevertheless it's very useful for what it can do, like flip through pictures in review mode and change the focus target point or even focus and take a photo. A camera this dependent on electronics does require power, and battery life for the E-M1 is so-so. Olympus claims 350 shots on a single charge but that's optimistic, especially if you rely on the monitor to compose shots, use continuous autofocus, turn on Wi-Fi, etc. Buy at least one extra battery when you order the camera.
My most serious complaint about the E-M1 is simply that the learning curve is steep, since there are so many options. And the user manual is as bad as every other camera's manual, which is to say, pretty bad.
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