The Sony SLT-A77 II is - as the name implies - an overhaul of the original A77, from 2011. The A77 Mark II features a new autofocus sensor, and it's much more than a refreshed version of an existing design. Instead the A77 II is built around the AF module with the most focus points of any camera on the market (79), covering an extremely wide area of the frame. It's also rated to work in lighting as low as -2EV. That doesn't necessarily make it quite as sophisticated at pro-grade DSLRs, since they have more cross and diagonal sensor elements, but it looks very impressive for a camera in this part of the market.

The autofocus capability combines with the camera's ability to shoot images at 12 frames per second to offer a compelling feature set. The A77 II also benefits from the autofocus tracking advances that have been included on recent Sony cameras, which use information from the main image sensor to identify and follow a given target.

Beyond that autofocus sensor, the A77 II gains an updated 24MP sensor (presumed to be a version of the sensor from the a6000, but without the on-chip sensor phase detection design) and all the benefits that the company introduced with its Bionz X processor. This means it gains three features: context-sensitive noise reduction, diffraction reduction technology and more-sophisticated sharpening.

Sony SLT-A77 II key specifications:

  • 24MP CMOS Sensor with gapless, offset microlenses
  • 12fps continuous shooting with autofocus (up to 60 JPEGs)
  • 79 point AF module with 15 cross-type AF points, covering 40% of frame
  • Increased control over AF behavior
  • 1080p60 movies with autofocus
  • Audio level monitoring during movie shooting
  • 2.4M dot OLED viewfinder
  • Pull-out three-hinge tilt/swivel 1.23m dot White Magic LCD screen
  • Built-in Wi-Fi with NFC
  • 1/8000th maximum shutter speed, shutter rated for 150,000 actuations
  • ISO 100 - 25,600 (Extendable down to 50, and up to 51,200 with multi-image combination)
  • Auto ISO customization
  • Optional, profile-based correction of vignetting, chromatic aberrations and geometric distortion
  • Top panel LCD
  • Stereo microphone and external mic socket
  • AF Micro Adjust

Focus advances

Although Sony stresses that the A77 II shouldn't be compared to pro-grade cameras (not least because it's much less expensive), it is starting to gain the kinds of specifications that - at least on paper - suggest it could be capable of punching considerably above its weight. For instance, the improvements to the A77 II's autofocus system extend a long way beyond the focus sensor itself.

The Mark II gains a range of subject identifying technologies that Sony has introduced in recent models. As such, it offers Eye-AF, rather than just face detection. It also gains the most advanced version of 'Lock-On AF' that we've yet seen, which will use or allow you to specify an off-center starting AF point (previously most Sonys assumed your subject was the thing at the center of the frame, when you started tracking).

Unlike the A99, which used its on-sensor phase detection elements to track a subject's movement when it was between the focus sensor's focus points, the A77 II uses the focus points adjacent to the currently active point. In addition, the A77 II becomes the first Sony that lets you determine how doggedly the camera should stick with the current focus point - an option you'd usually only expect to find on very high level models. Better still, it lets you specify different values for video and stills shooting.

On top of this, the camera has an A99-style distance limiter that lets you specify the approximate range of focus distance over which you expect your subject to travel, to prevent the camera being distracted by near or distant subjects. Also added is an option to prioritize release or focus in continuous shooting, giving much greater control over the camera's continuous focus and shooting behavior. Overall, the A77 II represents a major step forward for Sony autofocus control.

What's in a name?

Interestingly, Sony's marketing implies that it is moving away from the 'Single Lens Translucent' name for the A77 II, instead adopting the phrase 'Translucent mirror DSLR.' This is a slightly unfortunate phrase to use, semantically, but only because the mirror is actually semi-transparent (translucence normally implies a diffuse image): the camera has all the elements implied by the term 'DSLR.'

Side-note - a lot of people think 'reflex' in 'Single Lens Reflex' refers to a reflexive movement (of the mirror) but this is false. In this context it means reflection so a camera like the A77 with a non-moving mirror is still technically an SLR.

The technology remains the same as before: a fixed, semi-transparent mirror redirects a portion of the light up to a dedicated autofocus sensor, while the majority passes through to the main imaging sensor. The light lost to the AF sensor has a slight cost in terms of high ISO image quality, but avoids the complexity of multiple moving mirrors, with the benefit that autofocus remains available at all times, including during video shooting.

SLT-A77 II vs. SLT-A77 key differences


Sony SLT-A77 II

Sony SLT-A77
Body construction Magnesium Alloy/Plastic Magnesium Alloy/Plastic
Viewfinder 2.4m dot OLED TruFinder 2.4m dot OLED TruFinder
Rear LCD 1.23m dot RGBW LCD 920k dot RGB LCD
AF Sensor 79 points (15 cross-type) 19 points (11 cross-type)
GPS No Yes
Wi-Fi Yes No
LCD Articulation Triple hinged (hinge/tilt/swivel) Triple hinged (hinge/tilt/swivel)
Custom settings recall on mode dial 3 1
Hotshoe type ISO standard with Multi-Interface connections Minolta-style
Maximum shooting rate 12fps 12fps
Maximum shutter speed 1/8000th 1/8000th
Video 1080/60p (XAVC S or AVCHD) 1080/60p AVCHD