By Digital Photography Review
The E-M1 is the second model in Olympus’s OM-D series and extends the range further into semi-pro/enthusiast territory. There are two distinctions that set the E-M1 apart from its little brother (the E-M5) – a more sophisticated autofocus system and a ‘buttons for everything’ design approach. As such the two models will coexist, with the E-M1 sitting at the very top of Olympus’s lineup.
The biggest technological step forward on the E-M1 is the addition of on-sensor phase detection elements, giving the camera two distinct focus modes. The phase-detection system is used when lenses from the original Four Thirds system, which were designed for use that way, are attached. With native, Micro Four Thirds lenses, the camera will mainly stick with the contrast detection system that has proved so fast and accurate on the E-M5. Only if you use tracking AF will the camera utilize phase-detection information with a Micro Four Thirds lens.