Ten frames per second with continuously active AF is no mean feat, especially in a camera costing £700. Whether it is worth the loss of the optical viewfinder is another matter
Build and handling
So much about the Alpha 55 revolves around the use of translucent mirror, and this is especially true of the build and handling.
The technology allows Sony to pack all the camera’s features into an impressively compact 124.4x92x84.7mm body. The dimensions are identical to those of the Alpha 33 and, although the Alpha 55 has a similar depth to a conventional Alpha DSLR, it has significantly less height. This is achieved in part by using an EVF that does not need a prism, as optical viewfinders do.
The body sits nicely in the hand, with a rubberised front handgrip and curved thumb rest. The only difference is that the GPS capability, not found in the Alpha 33, is positioned next to the HDMI, external microphone and remote ports.
The body is made of lightweight polycarbonate and the build quality feels a little plasticky and more akin to an entry-level DSLR, but is still solid nonetheless. While the built-in flash has a rather modest output of GN 10m @ ISO 100, it can be used as a wireless trigger for Sony flashguns.
Those familiar with the Alpha range will note that the menu navigation remains the same. It is easy to move around it via the new fully articulated LCD screen (a first for the Alpha range). Operated from a hinge point at the bottom of the body, it can turn through 270° horizontally and 180° vertically.
The menu can also be navigated via the EVF and once I was able to memorise the key button layout of the body, I found I could operate it without taking my eye away from the viewfinder. The Function (Fn) button offers a host of controls, including metering and the autofocus area. Other key features such as dynamic range optimizer (DRO) and HDR mode have a dedicated button, while the panoramic sweep and 10fps modes have dedicated places on the shooting mode dial.
Shooting at 10fps is great fun, but it has some restrictions. Using a SanDisk Extreme Class 10 SDHC card, a 10fps burst in raw format lasts, at best, around 15 frames, which is 1.5sec compared to a 3.5sec burst of 35 frames when shooting Fine JPEG files.
When compared with the Canon EOS-1D Mark IV, the Alpha 55 allows a longer series of raw files to be captured, which is impressive, but a significantly shorter series of JPEG files. The EOS-1D Mark IV trumps the Sony model because it can shoot a sequence of up to 250 frames and is in a different class when it comes to JPEG image quality.
Once the Alpha 55’s buffer is full, there is a lag of around 20-25 seconds after shooting where the 10fps burst isn’t available. Having only a 1.5sec raw or 3.5sec JPEG image burst available at 10fps every 20-25 seconds is therefore not very flexible.