Technical innovation doesn’t always produce products people actually want to buy, but Sony’s digital cameras having been delivering the goods on both fronts recently. We’re tempted to say that the a7 is its greatest achievement to date.
At first glance it looks like a typical upmarket compact system camera (CSC). The SLR-like design with its angular viewfinder hump is a departure from previous NEX models (now going by the Alpha brand), and resembles the Olympus OM-D range. However, the big change is on the inside. While it uses the same E-Mount lenses as previous Sony CSCs, this is one of the first CSCs (along with the 36-megapixel a7R) to use a full-frame sensor.
It’s an important milestone in CSCs’ ability to challenge SLRs’ dominance among photography enthusiasts. It’s also an extraordinary technical achievement. One of the reasons why CSCs are smaller than SLRs is that they dispense with the lens mounts that were originally designed for full-frame cameras. The a7’s sensor barely fits behind its lens mount – the incoming light must be turning some tight corners inside the lens to cover the entire frame. The result is a full-frame interchangeable-lens camera that weighs 474g, or 769g with its 28-70mm kit lens. That’s a little over half the weight of a Nikon D610 or Canon EOS 6D with their kit zoom lenses.
The a7 will accept any E-Mount lens, but to shoot full frame it must be paired with one of the new FE models. There are currently five available. The FE 28-70mm F3.5-5.6 OSS is available with the a7 as a kit for around £1,500, or separately for £450. Alternatively, there’s the more upmarket FE 24-70mm f4 ZA OSS Carl Zeiss Sonnar T*, available for £1,050. Two primes are available: a 35mm f/2.8 for £750 and a 55mm f/1.8 for £930. The FE 70-200mm F4 G OSS telephoto lens is available to pre-order from Sony for £1,239.
It’s a very big sensor in a very compact body, here in comparison to an APS-C based Alpha
While the a7’s price is remarkably low for a full-frame camera, these lenses are expensive considering their specifications. Sony sent us the 55mm f/1.8 for testing, which isn’t far off the specs of 50mm f/1.8 lens available for SLRs for around £100. However, the optical performance of this 55mm lens is in a different league to those cheap SLR lenses, with extremely sharp details even when shooting wide open at f/1.8. If the other lenses in the FE range are anything like this one, their prices start to seem a lot more reasonable.
We accidentally took this photo at f/1.8 – something around f/8 would have probably been more appropriate to ensure the sharpest possible details. However, it’s really hard to fault the level of fine detail here
Sony a7 Features and handling
Sony has cut the size and weight but it hasn’t cut down on features. The 3in LCD screen tilts up and down, and the viewfinder is the same large XGA OLED display that we’ve been so impressed by on various other Sony cameras. The handgrip is much smaller than SLRs’ grips, but it’s nicely contoured and the a7 feels secure when held in one hand. The card slot is on the side rather than in the battery compartment, so it’s still accessible when shooting with a tripod.
There are dual command dials, a mode dial and exposure compensation dial neatly arranged on the top plate, plus a wheel on the back. In manual exposure mode, the command dials handle shutter speed and aperture while the rear wheel looks after the ISO speed. Leave the ISO speed on Auto and the exposure remains automatic for a shutter-and-aperture-priority mode, complete with exposure compensation. This is perfect for carefully controlling depth of field and motion blur without having to worry about the overall exposure level.