Sony today announced its latest translucent-mirror DSLR-style camera, the Alpha SLT-A57, which will replace the Alpha SLT-A55. The 16-megapixel, APS-C-sensored Alpha A57 is priced to compete with two popular midrange digital SLR cameras, the Canon EOS Rebel T3i and the Nikon D5100.
Unlike traditional DSLR cameras and pellicle/translucent-mirror SLRs such as the Canon Pellix from the 1960s, the SLT system uses a fixed internal reflex mirror to drive a continuous phase-detection autofocus system rather than an optical viewfinder; the Alpha SLT series lacks a through-the-lens optical viewfinder. Instead, you get a 1.4-million-dot eye-level LCD viewfinder and a tilting 3-inch LCD screen.
Like the higher-priced Sony Alpha SLT-A77 announced last year, the A57 boasts a very fast burst-shooting mode that runs laps around similarly priced DSLRs from Canon and Nikon, both of which cap out at around 4 frames per second. In burst mode, the A57 shoots 12 fps at an 8-megapixel resolution, or 10 fps at full 16-megapixel resolution with the aperture locked at its widest setting; the camera's burst mode drops down to 8 fps at full resolution with manual aperture control. In both burst-shooting scenarios, continuous autofocus and auto-exposure adjustments are enabled.
Video is likely to be a strong suit, as the A57 shares the A77's full 1080p video recording at 60 fps in AVCHD Progressive format. Full manual exposure controls are available in video mode, and the camera offers continuous phase-detection autofocus and auto-exposure adjustments while shooting in both burst mode and video mode.
In a Sony-provided head-to-head comparison chart, the Alpha A57 is billed as having a more-versatile autofocus system than both the Canon EOS Rebel T3i and the Nikon D5100, with 15 discrete autofocus points spread across three cross-sensors. Sony is also touting the Alpha A57's maximum ISO sensitivity of 16,000 and its motion-tracking autofocus system as competitive benefits.
Other in-camera tricks include a new "Auto Portrait Framing" feature that combines face detection and a "rule of thirds" algorithm to create a copy of a portrait photo, analyze the image, and automatically crop the photo to optimize shot composition.
Like most of Sony's Cyber-shot, NEX, and Alpha cameras, the A57 will include a motion-controlled Sweep Panorama mode, single-shot 3D and panorama 3D modes, and an exposure-bracketing HDR mode. The A57 is also Sony's first interchangeable-lens model to incorporate the company's "by pixel super resolution" digital zoom technology to eke out an additional 2X simulated zoom at the telephoto end of any A-mount lens attached, including fixed-focal-length lenses.
The A57's price, fast burst mode, and video options all add up to create an enticing camera option for budget-minded sports shooters and videographers. Due in April, the Sony Alpha SLT-A57 has body-based image stabilization and is priced at $800 as a kit with an 18-55mm zoom lens (27mm to 82.5mm in 35mm equivalent when attached to the camera) and $700 for the body only.