This review supplements the detailed 'First Look' at the OM-D E-M1 , which we published in September and focuses upon the new camera's performance in our standard suite of tests with the new M.Zuiko Digital ED 12-40mm f/2.8 Pro lens , which is reviewed separately.

The Olympus OM-D E-M5 was one of the most popular cameras of last year, owing to the combination of an impressive specification, attractive retro looks and excellent image quality. The E-M1 looks to pick up where the E-M5 left off.

Superb electronic viewfinder; Responsive AF system; Good image quality; Sturdy build

JPEG files somewhat over-processed

Back in 2012, when we reviewed the Olympus OM-D E-M5 we called it the "best Olympus compact system camera to date, and also a strong contender for best compact system camera full stop.

The OM-D E-M1 represents the best that Olympus has to offer in the compact system camera (CSC) market. It's a Micro Four Thirds-based, interchangeable lens camera that balances the needs of pros and enthusiast photographers in one neat, and solid package.

Strong build quality; Excellent controls; Excellent image quality; Fast performance

Shutter button too squishy for our liking; Some noticeable LCD and EVF flickering under fluro lights

The OM-D E-M1 takes over as the flagship camera for Olympus. It's a Micro Four Thirds-based camera with a stack of features that's aimed at those of...

Strong build quality; Excellent controls; Excellent image quality; Fast performance

Shutter button too squishy for our liking; Some noticeable LCD and EVF flickering under fluro lights

Image Quality Controls Customization Weather sealing EVF is best I've used

Not part of a lens bundle yet; Only had Body only

Olympus, for some awkward reason, chose an incredibly difficult naming scheme for its flagship mirrorless lineup, but moving past that, you realize there is something incredibly special about this camera.

Incredibly fast and accurate AF; Weather Sealed; Very useful EVF

High ISO performance can be dodgy; A little pricey

The E-M1 sits at the top of the Olympus CSC range, and the specs and the price reflect this. It's a solidly-built camera and the retro-inspired design is blended well with the contemporary technology.

Hang on, you might be saying; whilst the 16.3 effective megapixel OM-D E-M1 may outwardly resemble a DSLR it's not actually one in the strictest sense, on account of being a mirror-less model.

Solid feel build quality with dust and splash proofed body; in-body image stabilisation; image quality right up there with an actual DSLR to most eyes

Smaller imaging sensor than an APS-C DSLR; button and control layout is busy and can feel a little cramped at times

Fantastic replacement for the E5 and solves all of the issues I didn't like with the E-M5. Better build, weather sealing, built-in grip, better AF with FT lenses and slightly better video.