Sony Alpha SLT-A55VL review
23.4x15.6mm 16.0-megapixel sensor, 3.0x zoom (27-82.5mm equivalent), 441g
Sony's A55 and A33 stand apart from normal digital SLRs, and also from interchangeable-lens compact cameras such as the company's NEX-5. Our A33 review explains how these two cameras’ translucent mirrors define many aspects of their behaviour.
The A55 is the more expensive of the two, and justifies it with superior image quality, faster continuous performance and built-in GPS geotagging. It shoots at 10fps with continuous autofocus – a fantastic achievement that’s matched only by Canon and Nikon’s professional SLRs costing around £3,000. It was a little short-lived, though, slowing to 1.7fps after 24 JPEGs in our test. We also found that the autofocus struggled to keep up with fast-moving subjects. Even so, it beats anything else that this price for capturing fleeting moments of action.
It’s a responsive camera in normal use, but as with the A33 and NEX-5, that’s only if you’re prepared to live without an automatic image review function after taking a photo. Enabling this option meant that the screen went blank for about a second while the image was processed, and this slowed the shot-to-shot time from 0.5 to 1.3 seconds. This was annoying when using the LCD screen and worse when using the electronic viewfinder, as it’s such a far cry from the virtually uninterrupted view through an SLR’s optical viewfinder.
At least both of these screens – the articulated 3in LCD and the electronic viewfinder – are extremely high quality. The latter is as detailed as the optical viewfinders on consumer SLRs. Both screens predict exposure levels in manual exposure mode, dimming the live view image when a scene is under-exposed, and so on. That’s useful in most situations but was a disaster for off-camera flash work, where both screens became pitch black.
As with the A33, the A55’s video mode is almost great but it suffers even more from sensor overheating. According to Sony, videos last for just nine minutes at 20 degrees centigrade before the camera takes a self-imposed break. Deactivating image stabilisation helped, but in our tests, clips still only lasted for between one and 16 minutes, depending on how long we let the camera cool down for between clips.
Otherwise, using the A55 was largely plain sailing, with well-conceived controls that made it easy to adjust key settings. There’s no way to customise the Auto ISO mode but there are lots of other bells and whistles including in-camera HDR processing and panorama stitching. A Multi-Frame NR mode aligns and combines six frames to reduce noise, cleverly identifying areas of movement to avoid ghosting.
Image quality in our tests was acceptable but nothing special. Raw photos exhibited a wide dynamic range but noise was higher than we'd have liked, and higher than similarly priced SLRs from Nikon and Canon. Aggressive noise reduction did its intended job but also took its toll on details in JPEGs. The kit lens is disappointing, too, with chromatic aberrations giving poor corner sharpness.
None of these problems was fatal, though. We can well imagine the A55 with Sony 75-300mm telephoto lens being put to good use by wildlife enthusiasts or parents at sports field touchlines.
|CCD effective megapixels||16.0 megapixels|
|Viewfinder magnification, coverage||1.1x, 100%|
|LCD screen size||3.0in|
|LCD screen resolution||921,600 pixels|
|Zoom 35mm equivalent||27-82.5mm|
|Image stabilisation||optical, sensor shift|
|Maximum image resolution||4,912x3,264|
|Maximum movie resolution||1920x1080|
|Movie frame rate at max quality||25fps|
|File formats||JPEG, RAW; AVCHD, MPEG-4|
|Memory slot||SDXC, Memory Stick Pro Duo|
|Battery Life (tested)||380 shots|
|Connectivity||USB, mini HDMI, microphone, remote|
|HDMI output resolution||1080i|
|Lens mount||Sony Alpha|
|Focal length multiplier||1.5x|
|Kit lens model name||SAL-1855|
|Accessories||USB cable, neck strap|
|Exposure modes||program, shutter priority, aperture priority, manual|
|Shutter speed||30 to 1/4,000 seconds|
|Aperture range||f/3.5-22 (wide), f/5.6-36 (tele)|
|ISO range (at full resolution)||100 to 12800|
|Exposure compensation||+/-2 EV|
|White balance||auto, 6 presets with fine tuning, custom, manual|
|Additional image controls||contrast, saturation, sharpness, noise reduction, dynamic range, colour space|
|Closest macro focus||25cm|
|Metering modes||multi, centre-weighted, centre, face detect|
|Flash||auto, forced, suppressed, slow synchro, rear curtain, red-eye reduction|
|Drive modes||single, continuous, self-timer, AE bracket, HDR, sweep panorama, 3D sweep panorama, IR remote|