Sony brings a full-frame sensor to its SLT line with the Alpha A99
It took a few years to complete the transition, but Sony has completely phased out its traditional DSLR lineup. The company just introduced a new full-frame, translucent-mirror camera that will replace Sony's flagship Alpha A900 DSLR.
The new 24.3-megapixel Sony Alpha SLT-A99 has a full-frame CMOS sensor that measures 36mm by 24mm, which is about 2.3 times the size of the APS-C size sensors found in most consumer DSLRs. Compared to an APS-C-based DSLR with the same lens attached, a full-frame camera generally translates to three things: Phenomenal low-light and high-ISO performance, very shallow depth-of-field effects in macro shots, and extreme wide-angle capabilities.
According to Sony, the A99 is designed for both professional photographers and filmmakers; the new camera shoots 1080p video at up to 60 frames per second in video mode, and it also features manual exposure controls and support for an XLR adapter kit that can be used with professional-level microphones. Other high-end video features include full-time phase-detection autofocus while shooting movies, the ability to output video to a monitor while filming via HDMI, and a front-mounted knob on the front of the camera that can be used for quiet in-camera adjustments while recording video.
The A99 has body-based image stabilization and all the modes you'd expect in a high-end DSLR—RAW shooting, manual exposure controls, and ISO settings that reach up to 25,800—but it doesn't have a built-in flash or an optical viewfinder. The A99 also has the look and feel of a traditional DSLR, but there are a couple of key differences under the hood that distinguish it from its predecessor, the A900.
The big hardware change is that the Alpha A99 uses a fixed translucent mirror that directs light toward a dedicated phase-detection autofocus sensor rather than a through-the-lens optical viewfinder. Instead of the optical viewfinder found in a traditional DSLR, the A99 has a 2.3-million-dot OLED EVF, as well as a 3-inch adjustable LCD on the back.
This isn't the first Sony camera with the fixed translucent mirror—previous models such as the Alpha SLT-A57 and Alpha SLT-A77 also feature that technology—but it is Sony's first full-frame camera to use the system. Like the other translucent-mirror cameras in Sony's lineup, the A99 also has a peppy continuous-shooting mode. At full resolution, the A99 snaps 6 frames per second, and you can ramp it up to 10fps in the camera's APS-C crop mode with exposure locked on the first shot in a sequence.
The A99 is Sony's first camera to boast two phase-detection autofocus sensors: A dedicated 19-point sensor driven by the camera's fixed translucent mirror, as well as a 102-point phase-detection system on the imaging sensor itself. That dual-autofocus system powers two new focus modes that Sony is introducing in the camera: An "AF Depth" option, which lets the shooter limit the autofocus system to a specific distance from the lens, as well as an "AF Range" option that lets the shooter set a minimum and maximum distance for the AF system to work within.
You always pay more for a bigger sensor, and the Alpha A99 will be no exception when it becomes available in October. At $2800 for the body only, it's priced purely for the professional crowd, but it does come in at a lower price than full-frame DSLR rivals such as the Nikon D800 ($3000) and Canon EOS 5D Mark III ($3500).