Sony Unveils the a6400: Real-Time Eye AF and Tracking, World’s Fastest AF

Sony has just announced its latest mirrorless camera. The new a6400 features an impressive list of specs and features, including real-time eye autofocus, real-time tracking, and the world’s fastest autofocus.

Inside the a6400 is a 24.2-megapixel APS-C Exmor CMOS sensor backed by the latest-generation BIONZ X image processor. It has a maximum ISO of 32000 (expandable to 102,400) and can shoot continuous photos at up to 11 frames per second with the mechanical shutter or 8fps with silent shooting, both with full AF/AE tracking. The buffer can capture bursts of up to 116 JPEG frames or 46 RAW compressed frames.

One of the main strengths of the a6400 is its autofocus capabilities. The camera packs 425 phase- and contrast-detect AF points that cover 84% of the image area. Sony claims that the autofocus system is the fastest in the world, locking onto subjects in just 0.02 seconds.

The a6400 also introduces Sony’s new advanced “Real-time Eye AF” and “Real-time Tracking” features.

Real-time Eye AF is the latest iteration of Sony’s Eye AF tech. It uses AI-based object recognition to detect and track eyes, improving the accuracy, speed, and performance.

“In all autofocus modes, the camera now automatically detects the eyes of the subject and activates Eye AF with a half press of the shutter button, and when in AF-C or AF-A mode, the preferred eye (left or right) of your subject can be selected as the focus point,” Sony says. “Choices include Auto / Right Eye / Left Eye, and a Switch Right / Left Eye function is able to be assigned to a custom function as well.”

Sony will also be expanding the eye tracking to animals — a feature that could be invaluable for wildlife photographers — later in the summer of 2019 with a camera update.

Real-time Tracking also uses the same AI-based system to recognize subjects and ensure that they’re captured well.

“Real-time Tracking is a new object tracking function that keeps the most challenging moving subject in focus,” Sony says. “The ability to select any subject to be tracked while the shutter button is half-pressed provides new framing flexibility and allows the user to concentrate more fully on the image. If the subject is a person, AI is used to detect and keep track of the subject’s eye and face in real time for extremely high tracking precision.”

On the back of the a6400 is a 3-inch 921.6K-dot 180-degree tilting touchscreen LCD that’s perfect for selfies and vlogging.

Above the EVF is a 2.36-million-dot XGA Tru-Finder OLED electronic viewfinder.

For video, the a6400 can shoot internal UHD 4K with full pixel readout and no pixel binning. The camera collects “about 2.4x the amount of data required for 4K movies, and then oversamples it to produce high-quality 4K footage with exceptional detail and depth,” Sony says. 1080p Full HD can be shot at 120fps and up to 100Mbps.

Additional video features include S-Log2 and S-Log3, a Hybrid Log-Gamma (HLG) picture profile for an Instant HDR workflow, a built-in intervalometer for time-lapses, AE tracking (high, mid, and low), Zebra functionality, Gamma Display assist, and proxy recording.

Other features and specs of the a6400 include a pop-up flash, built-in Wi-Fi and NFC, 8 custom keys (with 89 different possible functions), enhanced menu usability, a help screen for menus, star rating for photos, a tough magnesium alloy build, and a shutter rated for 200,000 cycles.

Here are official sample photos captured with the Sony a6400:

Here are a couple of Sony videos introducing the new camera:

The new Sony a6400 mirrorless camera will hit store shelves and begin shipping in February 2019 with a price tag of $900. It’ll also be bundled with a 16-50mm f/3.5-5.6 lens for $1,000 or an 18-135mm f/3.5-5.6 lens for $1,300.