The Sony NEX-6 comes with a hybrid AF (auto-focus) system, which combines the phase-detection AF found in DSLR cameras and the contrast-detection AF found in compact and mirrorless system cameras. In theory, that should provide even better auto-focus, but it doesn't always work out - Canon's EOS M camera has really slow focusing speeds. However, it works out pretty well for Sony and the NEX-6, which has one of the fastest and most accurate auto-focus systems we've seen on a mirrorless camera. The camera consistently finds and locks onto the right subject, and there are very few times when you have to take over manually.
When it comes to images, we've found that the NEX-6 has the good ISO performance you'd expect from a modern APS-C sensor. Image noise is kept to a minimum up to ISO 1600, at ISO 3200 you start to see the noticeable effects of image noise and you should stop here most times. Image details clearly suffer if you push it up to ISO 6400, not to mention the more stratospherical ISO 12,800-25,600 range.
Colors look a tad muted to our taste, and the camera's rich LCD/EVF don't help - you can actually see the difference between the colors of what you're looking at versus what you just shot. The camera seems to underexpose by a tad, but DRO (Dynamic Range Optimizer) does a good job at preserving the highlights and boosting (a little) of the shadows. The images have that blurriness you'd get from a conventional APS-C sensor with an optical low-pass filter, unlike the sharpness you get from a camera without a filter like the Fujifilm X100S. But non-pixel-peepers, i.e. most of the population, should be happy with the images taken.
Note: These are sample photographs shot with the Sony NEX-6. They were shot with Noise Reduction turned off and saved in the AdobeRGB color space. otherwise the photos have not been post-processed. They are copyright to SPH Magazines, are provided for your reference only and we ask that you do not reproduce them elsewhere. Click for full-resolution images.
Using the Sony NEX-6 was more like using an APS-C DSLR camera than we'd expected. Like a DSLR, the NEX-6 has a control dial and rear control wheel which makes it easy to switch manual settings like aperture and shutter speed. The NEX-6 doesn't have the wealth of dedicated buttons you'd find on a DSLR, like a AF/MF switch, but it is much smaller, lighter and easier to carry than a DSLR camera.
The electronic viewfinder surely adds to the DSLR-like experience, as does the APS-C sized sensor inside, which offers comparative image quality to APS-C DSLRs today. Auto-focus is fast and accurate, and you'd hardly find yourself needing to use manual focus - but in case you do, manual focusing is made easy with focus peaking and focus magnification. If we have one complaint, it's that the menu interface is inelegant and pretty much the same since the first NEX was released. It helps that with the NEX-6 we could assign essential settings to the Fn (Function) button, but the NEX series could use a UI overhaul.
As a single camera purchase, you can hardly go wrong with the Sony Alpha NEX-6. However, we offer the same caveat whenever we recommend a NEX camera, the weakness isn't in the camera as much as it is in the lenses; there just aren't many fast lenses for the enthusiast. We count 13 lenses listed on Sony's website, while Micro Four Thirds has 38. If you're looking to buy into an eco-system, you'll need to take a broader view to see if the E-mount is for you.