REVIEW : sony alpha a99 II
Sony’s put so much effort into its A7 mirrorless camera range that many might have forgotten about the SLR-like Alpha range. But it’s back…
SLT / £3,000 / $3,200 (body only) / sony.com
These are exciting times for Sony fans – and confusing, too. Just when we all thought the A7 series was the future, the company drops a bombshell. The a99 II is a throwback to Sony’s early experiments in DSLR alternatives. It’s like a mirrorless camera… but with a mirror. In fact, it’s a fixed, translucent mirror, which passes light through to the sensor at the back, but also feeds a dedicated SLR-style phase detection autofocus sensor in the base of the pentaprism housing. It doesn’t actually have a pentaprism, though. Instead, it uses an electronic viewfinder fed by the main sensor. The aim of the SLT (single lens translucent) design is to combine the
The a99 II is like a mirrorless camera… but with a mirror. A fixed, translucent mirror.
autofocus speed of a SLR with the always-on electronic live view of a mirrorless. Sony has insisted more than once that the Alpha format is alive and kicking, despite the development of the A7 series, and here’s the proof. The a99 II has the second-highest resolution of any full-frame camera at 42.4 megapixels, and can shoot at this resolution at up to 12fps. So it’s within a whisker of Nikon D5 and Canon EOS-1D X II speeds, but with double the resolution. There are some caveats. It doesn’t have the buffer capacity of these cameras, though it can still capture around 50 RAW+JPEG images. And AE/AF tracking in the 12fps H+ modes does need compatible lenses. It’s also possible to shoot in live view at 8fps (H mode). So far it sounds as if this should all have been technically possible with the Sony A7R II as a platform, but the a99 II has a second major selling point: a brand new 79-point/399-point hybrid phase detection AF system that’s only possible with the Alpha SLT design. The 79 points are provided by the dedicated phase detection sensor above the mirror and are arranged in a typical SLR distribution around the centre of the frame. The further 399 points are onsensor phase detection points arranged in a rectangular area over a much larger area of the screen. These two systems work together, depending on the autofocus mode you select. Fifteen of the 79 AF points on the dedicated AF sensor are cross-type, but the remainder overlay corresponding AF points on the main sensor to provide a kind of hybrid cross-type AF. Beyond this 79-point area, the on-sensor AF points can pick up subjects moving quickly and erratically around the frame. They all form part of Sony’s 4D focus system – lateral and vertical movement, depth and time ( predictive autofocus). The 42.4MP sensor has no anti-aliasing filter, and in our lab tests the a99 II equals the resolution of the Canon EOS 5DS. It’s matched up with a BIONZ X processor and front-end LSI that delivers widely expanded sensitivity (up to ISO25,600, or 102,400 in expanded mode), extra-low noise (with area-specific noise reduction) and even diffraction compensation at smaller lens apertures. The a99 II also incorporates in-body 5-axis image stabilisation and impressive video capabilities, which include full-frame 4K movies or high-resolution oversampled 4K without pixel binning in the Super 35mm format.
Build and handling
In the flesh, the a99 II is surprisingly unremarkable. Despite the many technical advances, the a99 II is actually eight per cent smaller than its predecessor. The battery life expectancy is a reminder that mirrorless cameras (even those with a mirror!) gobble up power much faster than an SLR. The a99 II’s battery is good for just 390 shots in live view and 490 using the EVF. You’re going to need plenty of spares if you go out on an extended shoot, and you’ll need to make sure they’re all charged up first. There’s an optional battery grip which will help with the power management, and if you like the bigger, meatier dimensions of pro SLRs like the EOS-1D X and Nikon D5, then this might be a good buy. Without the grip, the a99 II is nicely compact. If compact is what you want. Fit a pro-spec zoom like the Zeiss 24-70mm f/2.8, however, and you might wish the body had a bit more vertical height, for a better grip in the hand to balance out some of these big, professional lenses. The thumbstick on the back is something of an acquired taste, too. It’s used extensively for menu navigation and focus point positioning, but it has a short throw and a heavy, rather imprecise feel. The electronic viewfinder is terrific, though. It’s so crisp and responsive that, given the fact the a99 II already handles like a SLR, you could forget it’s not an optical viewfinder. The only thing that gives it away sometimes is when shooting
outdoors under a bright sky – overexposed areas are clipped in a typically digital way, whereas with an optical viewfinder it’s your eye that’s doing the ‘seeing’. The rear screen is especially clever. It has a tilt mechanism with an additional cantilever section that lets you angle the screen higher and further forward for waist-level shooting. It also hinges at the base for overhead shots, and there’s a central pivot here, which lets you turn the screen sideways too. This means vertical shots are as straightforward as horizontal ones (something you don’t get with a regular tilting screen) and without the awkward sideways extension of regular variangle screens. Neither is the a99 II’s live view mode the clunky, slowed down experience you get on a conventional SLR – this is a camera that’s as effective in live view as it is in viewfinder shooting.
Our real-world tests confirm the results we got in the lab – the a99 II’s 42.4MP sensor can deliver extremely sharp results. However, you do have to work that little bit harder to get the best from it, because its resolution shows up the slightest focusing errors or camera shake. With a camera like this, it’s tempting to zoom in on every image to revel in the detail or, worse, to find fault either with your equipment or your technique. This means the 5-axis stabilisation is especially welcome. Even so, if you’re shooting handheld, you might want to keep the shutter speeds just a stop or so higher than you would with a lower-res model. The colour rendition, dynamic range and exposure accuracy are hard to fault. Any exposure variations were entirely predictable and due to the scene lighting, not any failings on the part of the Sony’s metering system. The a99 II delivers great-looking JPEGs, though most pros will be shooting RAW and will make their own decisions about white balance, colours and tonal rendering. It’s one thing combining high frame rates with high resolution, but photographers also need good high ISO performance, and this is a stumbling block for high-res sensors. There comes a point where a combination of detail loss, noise and smearing makes an image unusable. The a99 II does pretty well in this respect too, delivering images with little real degradation right up to ISO3,200. Beyond this, the noise stays well controlled but detail loss and smearing starts to creep in. There’s a clear difference between ISO3,200 and 6,400, and at ISO12,800, finer detail starts to get distinctly mushy. The image quality isn’t intolerable even at the maximum expanded ISO102,400 setting, but you’d only use it in an emergency, and with the awareness that you came with the wrong kind of camera. The autofocus system is highly effective, though complicated by the fact you need a compatible lens to get the benefit of the Hybrid Phase Detection AF system with wide focus area, 399 AF points and Hybrid Cross AF. Many are compatible, though, and there’s a list on the Sony website. If your lens isn’t on that list, you’re restricted to the regular 79-point AF sensor above the mirror. Assuming your lens meets those criteria, you have a choice between Wide (effectively, automatic AF point selection), Zone (effectively, selecting a smaller area for auto AF point selection), Center, Flexible Spot (you choose your AF point manually) and Expanded Flexible Spot (use this for larger subjects or to allow for some subject movement) modes. When Lock-On AF is used – when you half-press the shutter release in continuous AF mode – the camera will automatically track moving subjects within the zone you’ve specified. Once you understand the principle, it’s perfectly logical, and effective too. Focus acquisition appears rapid, though this will depend on the lens you’re using – some have faster AF actuators than others – and the focus-tracking worked well in our tests. Complex AF systems take time to learn and test properly, however, requiring the opportunity to try them out in a wide range of scenarios. The signs look good for Sony’s Hybrid Phase Detection AF system, but so far we’ve only been able to try it out in a relatively undemanding motorsport scenario with fast but predictable subject movement. The Sony Alpha a99 II is certainly an exciting camera. Physically, it lacks the bulk and grippability of the Nikon D5 and EOS-1D X, but its combination of frame rate, resolution and autofocus sophistication is highly compelling.
The a99 II sports a regular mode dial but a locking button prevents it from being moved accidentally. The continuous shooting modes don’t get a dedicated external dial, however. The ISO button behind the shutter release has a concave profile to make it easier to distinguish by touch from the raised EV compensation button to its left. The a99 II takes regular A-mount lenses, but not all are compatible with its Hybrid Phase Detection AF system.