Sony a7R Full-Frame Mirrorless Digital Camera

The a7 and a7R are identical in terms of physical design, with the main differences being the sensor and autofocus system. The a7 features a full-frame 24 megapixel CMOS, while the a7R has a 36 megapixel CMOS sensor with no optical low-pass filter. The a7 uses a Hybrid AF system (with on-chip phase detection) similar to the one found on the NEX-6, while the a7R has traditional contrast detection. The a7 is also capable of electronic first curtain mode, which allows for a quieter shutter, and reduces the potential for 'shutter shock' vibration; this is absent from the a7R. Both cameras use Sony's latest Bionz X processor and also have XGA electronic viewfinders, tilting LCDs, Wi-Fi, and weatherproof bodies that resemble that of the Olympus E-M1. Here's a quick summary of the differences between the a7 and a7R:

As you'd expect, Sony had to come up with new lenses to take advantage of the full-frame sensors, and they'll be known as 'FE-series'. Five lenses were announced to start with (listed below), with ten more promised by 2015. Existing E-mount lenses will work, though the image will (necessarily) be cropped. If you have A-mount lenses laying around, those too will work, as long as you pick up either of Sony's full-frame-ready adapters (the LA-EA3 or LA-EA4). Sony a7R key features 36.3 megapixel full-frame CMOS sensor with no OLPF E-mount with support for FE, E, and A-mount lenses (with adapter) Bionz X image processor Sealed magnesium alloy body Built-in Multi-Interface hot shoe 3-inch tilting LCD with 1.23 million dots (640x480, RGBW) XGA (1024x768) electronic viewfinder Diffraction correction technology Continuous shooting up to 4 fps Full HD video recording at 1080/60p and 24p; uncompressed HDMI output Wi-Fi with NFC capability and downloadable apps While the a7R is really focused on still image quality - due to its high resolution sensor without an AA filter - it's also quite adept at video recording. It records at 1080/60p and 24p, with manual exposure control, headphone and mic ports, an audio meter, zebra pattern, XLR support (via adapter), and live, uncompressed HDMI output.

Bionz X Processor The company's latest processor, dubbed Bionz X for reasons that presumably made sense to someone, is considerably more powerful than the previous generation, allowing what the company says is more sophisticated processing. Sony is being a little vague on specifics but is touting the new processor as offering 'Detail Reproduction Technology' which appears to be a more subtle and sophisticated sharpening system. The company promises less apparent emphasis on edges, giving a more convincing representation of fine detail'. Another function promised by the Bionz X processor is 'Diffraction Reduction', in which the camera's processing attempts to correct for the softness caused by diffraction as you stop a lens' aperture down. This processing is presumably aperture-dependent and sounds similar to an element of Fujifilm's Lens Modulation Optimization system (introduced on the X100S), suggesting it's something we should expect to see become more common across brands in the coming months. Finally, Sony says the Bionz X chip offers a more advanced version of its context-sensitive, 'area-specific noise reduction', which attempts to identify whether each area of an image represents smooth tone, textured detail or subject edges and apply different amounts of noise reduction accordingly. Later in the review, we'll show you just how well this system works, and also the problems it can create.

Lenses While the a7R has an E-mount, you'll need to use Sony's new FE-series lenses to take advantage of its full-frame sensor. Existing E-mount lenses will still physically fit, but as they're only designed for use with APS-C sensors, their image circles won't cover the entire frame properly (just like using Sony's DT lenses on full-frame Alpha mount cameras). While five FE lenses were announced at launch, the 70-200mm F4 lens wasn't available to test alongside the camera. The 28-70mm F3.5-5.6 OSS will only be sold as a kit lens for the a7. All of the lenses are weather-sealed, but while the zooms include optical stabilization, the primes do not. Here are the five FE lenses that have been officially announced: