The Sony ILCE-7, ILCE-7R and ILCE-7S (α7/α7R/α7S) are three closely related digital cameras announced 16 October 2013 and 6 April 2014. They are Sony’s first full-frame mirrorless interchangeable lens cameras and share the E-mount with the company’s smaller sensor NEX series. They are targeted at experienced users, enthusiasts and professionals.
Sony's new model naming prefix strives to unify model names. “ILC” indicates Interchangeable Lens Camera followed by an indicator of A-mount “A” or E-mount “E”
The products are more commonly known as the α7, α7R and α7S. Pre-announcement rumours speculated that the new camera would be named Sony NEX-9.
Although the α7 and α7R use full frame sensors and have a DSLR-shaped design, their sizes and weights are less than Olympus OM-D E-M1 with its small micro four thirds sensor and can also be compared with the lightest Full-frame DSLR. Compared to the smallest and lightest APS-C DSLR Canon EOS 100D, the α7 is 67 grams heavier and a bit larger, but the thickness is only two thirds of Canon's. The α7 price is significant lower than a comparative Full-frame DSLR price, but still higher than that of a low or mid-end compact camera price. Compared to the Nikon D800E, the weight of Sony α7R is only about a half and the price is about two-thirds, a maximum image quality in a compact body, but lacks of built-in stabilization, slower Single AF and Continuous AF, and has no built-in flash.
There are three different types of cameras available in the α7-series. They are the α7, α7R and α7S.
The 'R' model is the "resolution" version of the series with a new, higher-density sensor design, and priced $600 more than the α7 at launch, but has no optical low-pass filter as the sibling has. However, the α7R does not include the faster hybrid auto-focus system found on the lower-resolution model.
The 'S' model is a high sensitivity version of the series with an effective ISO range from 100 to 409600 and with 4K video capability.