Sony Alpha SLT-A99 In-Depth Review
The Sony SLT-A99 is the Japanese camera maker's flagship model, aimed squarely at DSLR enthusiasts who will settle for nothing less than a full frame sensor in a rugged body with a plethora of external and customizable controls. It arrives almost four years after its predecessor, the A900, the company's first full frame DSLR. You'd certainly expect significant new features given such a long gap between products and Sony has lost no opportunity to equip the A99 with every bit of electronic expertise they've incorporated into their NEX and SLT models in the interim. Whereas the A900 was a defiantly conventional SLR that would have been immediately familiar to Konica Minolta film-camera users, the A99 is something of a technological tour-de-force.
Start with a dual chip AF system, live view focus peaking, tiltable rear LCD, built-in GPS and 1080p60 movie recording plus the ability to output uncompressed video, and the contrast to the stills-only A900 couldn't be more stark aside from the A99's identical 24MP resolution. And then of course, there's the fact that with the A99 Sony has opted for an electronic, versus optical viewfinder. From a features standpoint, it's clear that Sony was out to rethink its approach to the enthusiast market and attempt to lure would-be DSLR shooters with a surfeit of technology while broadening its appeal to videographers.
Like its predecessor, the SLT-A99 enters a full frame DSLR playing field still dominated by the 'big two', so the camera's success will depend not just on its advances over the A900, but how well it competes against the Canon EOS 5D Mark III and Nikon D800. Sony may have chosen not to challenge the 36MP Nikon D800 for pixel count - somewhat of a surprise given that the D800 houses a Sony-made sensor - but has opted instead for a unique dual sensor AF system that promises more precise subject tracking along with a 6fps continuous AF burst rate.
Sony has gone to great lengths to stress the work that has gone into improving the camera's image quality. The latest 24MP sensor has been designed so that more of each photosite is light-sensitive. The electronics in front of this light sensitive region have been slimmed-down to increase the angle from which each site can receive light. These changes, combined with a design that provides a short and high-capacity path between the sensor output and the image processor, and the addition of 14-bit Raw output, should mean improved still image quality.
The rapid adoption of DSLRs by video professionals has made HD recording with manual exposure control a stock feature in even mid-range models. With the A99 though, Sony leverages its considerable video expertise by combining 1080p60 video capture with SLT-enabled phase-detection AF along with the ability to output uncompressed video over HDMI (a feature we first saw in the Nikon D800). Another well-implemented nod to the needs of run-and-gun videographers can be found in the inclusion of a 'silent controller' that allows for adjustments to made while recording without the attendant button clicks.
Sony SLT-A99 key specifications:
- 24MP full-frame CMOS Sensor with on-chip phase detection AF
- Fixed-mirror design SLT
- 2.4M dot OLED electronic viewfinder
- 14-bit Raw output
- ISO 100-25,600
- Up to 6 frame-per-second continuous shooting with AF
- ISO-compatible flash hotshoe with 'multi interface' expansion connector
- Pull-out three-hinge tilt/swivel 1.23m dot RGBW LCD screen
- Top panel LCD
- Microphone and headphone sockets
- Built-in GPS
- AF Micro Adjust
The A99 is based around Sony's SLT design - a variant on the DSLR concept that uses an electronic viewfinder (EVF), rather than an optical one. Instead of having a mirror that has to flip out of the way to to take a photo, it uses a fixed semi-transparent mirror that redirects light (with negligible luminance loss) to a DSLR-style phase-detection autofocus sensor. This means live view and autofocus are always active and that the A99 can offer a consistent shooting experience whether you use the flip-out screen or the EVF. It also means the conventional 19-point phase detection focus sensor is always illuminated, along with the 109-point on-sensor array. This puts the A99 in the unique position of having dual phase-detection focus systems available at all times - an unusual feature that Sony has developed several features to exploit, including 'AF-D', its depth-map assist continuous AF feature.
The decision to build a full-frame SLT camera will certainly be controversial among enthusiasts who equate a 'serious' camera with an optical, rather than electronic viewfinder. It's worth pointing out though that the A99 sports the same 2.4M dot resolution OLED 'Tru-Finder' EVF whose performance we found so impressive in our NEX-7 review. And the benefits that an EVF provides, including exposure and white balance preview, focus peaking and a customizable information overlay, all without removing the camera from an eye-level shooting position, may be enough to sway those who spends even a little time actually using it.
This video, shot at the Photokina trade show earlier this year is taken from our previously published preview of the Sony SLT-A99.