Preview Sony SLT-A57

review based on a pre-production Sony SLT-A57

Sony's original SLT models - the A55 and A33, showed the company was willing to try something different to compete with the well-entrenched SLR makers. With the SLT-A57, it looks like Sony is intent on competing more fiercely than ever. The specs may hint at a gentle update but, from what we've seen, it's an overall package that DSLR makers should take seriously.
For a start, it's based around the excellent 16MP sensor seen in many of the best current DSLRs and features a body more like the A65. But it also offers to make its wide range of features more easily accessible than before, helping the first-time user to get the most out of the camera.
We've enjoyed using the SLT cameras we've used so far. Concerns about light-loss, electronic viewfinders and ghosting may have made DSLR purists nervous, but most people who tried using the cameras couldn't help but be impressed. Having light constantly directed to the AF sensor meant the SLTs could offer autofocus both during video shooting and 10 frame-per-second shooting - a combination still unmatched at the consumer end of the market.
Even if you don't need any of the tricks its design allows, the fixed, semi-transparent mirror design also allowed Sony to make good on its ambitions of cameras that offer a seamless shooting experience whether shooting SLR-style or in live view. And this is an ability that shouldn't be under-appreciated - even if you're only used to shooting through a viewfinder, being able to shoot using the rear screen and have consistent operational behavior and speed is a real bonus.
The A57 can still shoot at 10 frames per second (or 12fps in an 8.4MP cropped mode), but it gains the ability to shoot 1080p video at 60 or 24 fps (50 or 25 on European models) and the high-contrast edge enhancing 'peaking' mode for manual focusing in video and with non-AF lenses. It also gains the now expected image processing 'Picture Effects,' such as retro, pinhole and miniature filters. But, more significantly, it gains the 'Clear Image Zoom' digital zoom mode that uses an image database to 'intelligently' interpolate between captured pixels to give full resolution output.
Making practical use of this ability, the A57 also has a mode that will re-process your people pictures with what it thinks is a better composition. It does this by searching for faces and re-cropping into portrait orientation with the subject's eyes positioned according to the rule-of-thirds. The crop is then re-sized back up to 16MP, using the Clear Image Zoom scaling.
The viewfinder, like the A55's, is still an LCD rather than the high-resolution OLEDs used in the more expensive models but even this has been tweaked. The magnifying optics in front of the LCD panel have been redesigned to allow more of the screen to be seen. There are also two magnification modes within the viewfinder, designed to change the eyepoint (viewing distance) of the finder to make life easier for users with glasses.

Key Specifications:

• 16.1MP CMOS sensor
• Latest Bionz processor
• Larger, FM500H battery (same as A65 and A77)
• ISO 100-16000
• Auto ISO 100-3200
• 1,440,000 dot LCD electronic viewfinder
• 920,000 dot bottom-hinged rear LCD
• 10 frame per second continuous shooting mode with AF (12fps at 8.4MP crop)
• Picture Effects processing options
• Clear View Zoom up-sizing digital zoom
• Peaking manual focus guide overlay
• 1080p AVCHD 2.0 movies at 60 or 24 fps (50 or 25 in Europe)

Compared to the SLT-A55

It should be immediately obvious that the A57 is a much larger camera than the A55, with Sony perhaps deciding not to draw so much attention to the differences between its SLT cameras and the DSLRs it'll sit alongside on the shelves.