Introduction and features
After the introduction of the Sony Alpha 7 II and Sony Alpha 7R II it was only a matter of time before Sony introduced the update to the Alpha 7S, its 12Mp, low light and video-centric model which has become popular in the film and television industry. Sure enough, the Alpha 7S II was announced in September 2015 and is now on sale.
While the changes brought by the new camera are welcome, its specification sheet holds few surprises, featuring many of the upgrades already seen elsewhere in the Sony A7 range.
For example, like the A7R II, the A7S II can record 4K 4:2:0 8-bit video (in XAVC S format and with no pixel binning) to a suitably fast memory card and it has a 5-axis stabilisation system.
Pixel binning combines the output from a small grid of pixels and it’s a way of getting higher sensitivities from a sensor at the cost of a lower resolution.
Like the A7S, the Mark II can also record 4K video to an external recorder like the Atomos Shogun via HDMI with 8-bit 4:2:2 colour depth.
Having 8-bit colour means that there are 256 shades of each primary colour, which may sound good but it doesn’t compare so well with recording externally to a 4K recorder from a Panasonic GH4 as its 10-bit output gives 1024 shades per colour.
One significant first scored by the A7S II for the A7-series, however, is the ability to record full HD footage at up to 120fps at 100Mbps (without pixel binning) for super-slow motion playback.
The A7S cameras are also designed for low-light shooting and as before, the maximum sensitivity setting is ISO 409,600. The native range is ISO 100-102,400. There’s also the 5-axis image stabilisation system that we’ve seen and appreciated in the A7 II and A7R II, for smoother footage and sharper images.
Like the original A7S, at the heart of the A7S II is a full-frame 12.2Mp Exmor CMOS sensor. According to Sony’s Masaaki Oshima, Deputy General Manager of the Digital Imaging Business Group’s Imaging Products and Solutions Sector, the new camera uses the same sensor and processing engine as the A7S, but new circuitry along with improved noise reduction algorithms mean that noise is controlled much better than before. It’s also been optimised for video recording.
Sony has increased the number of autofocus points available from 25 on the A7S to 169 with the new camera. It also claims a 2x faster AF response in video mode. It still relies on contrast detection autofocus, however, and unlike the A7 II there’s no phase detection element.
Sony’s Picture Profiles are available to allow videographers to tailor the appearance of video (and stills) in-camera. These make it possible to set specific values for Black Level, Gamma and Knee (highlight compression) as well as colour adjustment (Color Mode, Color Level, Color Phase and Color Depth) and Detail.
The Gamma settings include Sony’s S-Log2 as well as the new S-log3 setting. These can increase dynamic range by up to 1300% by creating very flat looking footage that is ideal for post-capture grading. S-Log2 is designed with highlight preservation in mind while S-Log3 helps capture greater tonal range in shadows and mid-tones.
There’s also a helpful new Gamma Display Assist option that lets you see the scene with natural contrast even though you’re shooting with an S-Log gamma setting.
As usual, focus peaking, zebras and a histogram can be made visible to aid focusing and exposure.
The only thing really missing from the A7S II compared to Sony’s professional large sensor video cameras is built-in neutral density filters. As with other video SLRs/CSCs you will need to add a neutral density filter to your lens so you can use wide apertures for shallow depth of field while keep shutter speed to 1/50sec or longer.
Build and handling
Like the A7 II and A7R II, the new A7S II feels well made and is comfortable to hold, with most controls being within easy reach. The new camera is tougher than the original model, with more magnesium alloy and a reinforced lens mount. It’s also weatherproof, although you need to watch out for rain droplets getting onto the viewfinder sensor and switching off the rear screen when you don’t want it to.
In response to criticisms of the design of the original A7, A7R and A7S, Sony has made changes to the Mark II versions. These include making the grip bigger, moving the shutter release forward on to the top of the grip and changing the rear barrel-like dial to a more standard, semi-recessed type dial.
Unfortunately the video record button is still on the corner of the thumb-grip on the back of the camera and it’s awkward to locate and press when holding the camera. Thankfully there are plenty of customisation options so it can be set to another button. Those who want to use the A7S II primarily for stills may find one of the two customisation buttons on the top-plate a good choice, while dedicated videographers may prefer to use the large button on the back of the camera at the centre of control dial and navigation pad. This button makes a good choice for accessing the focus point setting mode for stills shooters.
While the customisation options available are generally very good, there are some frustrations, as the list of available functions varies a little between the buttons. Metering mode, for instance, can be assigned to any of the navigation buttons and Custom buttons 2, 3 and 4, but not Custom button 1. The rear dial also provides a convenient means of scrolling through the huge sensitivity range quickly, but the right navigation button is actually marked ISO.
The main menu layout is largely the same as the A7R Mark II’s and it could be improved by the presence of a customisable screen as well as greater separation of the video and stills options. Similarly, while it’s great to have a customisable Function menu, it would be helpful to have two; one for stills and one for video.
It would also be nice to have a more direct route to the autofocus points with a mini joystick controller like on the Canon 5D Mark II and Canon 5DS or a dedicated pad like on cameras like the Nikon D7200 and D810.
Sony’s XGA OLED Tru-Finder is excellent and there’s no trace of smudging or stutter when panning to follow a moving subject. It provides an impressive view when composing images with the camera held to your eye, with a shimmer of noise in low light. As most professional video shooters will focus manually with the A7S II, it’s especially helpful that it enables the image to be magnified to check sharpness even when shooting – something that competing cameras like the Panasonic GH4 can’t. The only odd thing is that the magnification isn’t as clear in video mode as when shooting stills.
Further good news is that its preview in the viewfinder and on the screen is a good match for the captured image.
Performance: stills and video quality
As it has a lower pixel count than the A7R II and A7 II, the Alpha 7S II can’t resolve as much detail as its stablemates in stills, but there is enough information to make high-quality A3 prints. In addition, its larger photosites really help with noise control and while you wouldn’t want to use ISO 409,600 routinely, if you’re reporting events in near darkness you’ll get something just about recognisable – just as you would from the original A7S.
• The tilting screen is useful for composing low-level images, though it can be partially obscured by the electronic viewfinder. Click here for a full size version.
• Despite the bright sky the camera delivered a perfect exposure by itself here, but it’s handy to have the exposure compensation dial within easy reach. Click here for a full size version.
Dropping back within the native range to ISO 102,400 produces more acceptable results with granular noise that has no banding or clumping. When shooting stills it’s best to keep sensitivity to ISO 25,600 or lower to avoid noise being clearly visible in even-toned areas at normal viewing sizes. Meanwhile videos remain more generally usable when shot at up to around ISO 6,400.
Comparing images with those from the original A7S reveals that the level of detail is very similar, but mid-to-high sensitivity JPEGs have slightly more fine-texture noise visible at 100%. The simultaneously captured raw files have less obvious noise which appears finer grained than in raw files from the A7S. Very high-sensitivity images (JPEG and raw files) look the same from both cameras with respect to noise, but the newer model produces slightly more muted colours throughout the ISO range and does a better job with reds.
In the lab the Mark II camera scored about the same or slightly worse than the original model for stills, which can be taken as confirmation that the A7S II has been further optimised for video. Comparing video footage from the two cameras reveals that their performance is very similar apart from in low light when the new camera produces very slightly better results.
Red is handled better by the A7S II than it is by the original A7S. Click here for a full size version.
• The auto white balance system has coped well with the fluorescent lighting of the bakery in this indoor market. Click here for a full size version.
The A7S II’s colour reproduction is better than the A7S’s in low light. Most other cameras lose colour information in super low light, but the A7S II does an impressively good job of hanging onto it.
The quality of the 4K XAVC S video is very impressive and close to that from Sony’s larger professional-level video cameras with 10- or 12-bit outputs. The difference is in the amount of colour information and detail in highlights and shadows – even when using the S-Log2 and S-Log3 settings. The A7S II can’t quite match it, but it’s not very far off despite having just 8-bit output.
Rolling shutter, or jello-effect is also still an issue. It’s fine with walking-pace movement, but move up to 30mph or faster and there’s noticeable skewing.
When shooting with the Standard Creative Style and auto white balance settings selected in overcast conditions the A7S II tends to produce slightly dull JPEGs and movies, lacking a little saturation and warmth. Switching to the Vivid Creative Style usually produces more pleasing tones, though some colours may be pushed a bit too far and it’s worth experimenting with the customisation options. In natural light the Daylight white balance settings tends to produce more pleasing tones – not that this makes much difference when you’re shooting raw files.
Samples provided by Dan Chung. Dan is editor of Newsshooter and has over 20 years of experience working behind a camera. His career started in photography but evolved into documentary, multimedia and broadcast TV. He shot the first news video on a DSLR and has been on staff at Reuters, The Guardian and CNBC.
Slow burn: Sony a7S II shoots 120 fps in low light with Zeiss Loxia 21 and Milvus lenses
Steve Rawlings juggles for a living. In this slow motion test of the Sony a7S II he tells about how he accomplishes his feats with fire. It was shot internally to SD card in 120fps at 1080p using the 2.2x crop mode for better quality. ISO ranged from 1600 to 6400 depending on the lens used.
The lenses used were the Zeiss Loxia 21mm f2.8, and Milvus 50mm f1.4 and 100mm f2.8 macro with a Metabones EF to E-mount adapter. Interview audio was recorded into the a7S II using a Rode Reporter mic and XLR-K2M audio adapter.
It was shot in S-Log 2, S-Gamut, edited in Premiere Pro and graded using FilmConvert.
Sony a7S II vs a7S 4K high ISO noise tests
At the recent Sony event I attended in Germany Newsshooter compared the a7S II and original a7S cameras side by side in a relatively controlled environment with a model. Both cameras were set in tungsten white balance, S-Log 2, S-Gamut and set to record 4K ProRes HQ externally to an Atomos Ninja Assassin for optimal image quality. The lens was a brand new Canon-fit Zeiss Milvus 50mm mounted on a Metabones MkIV Smart Adapter.
Please note that the a7S was accidentally set at +1 Magenta – which should in theory should have made it less green. Even with this correction it still appears green next to the a7S II.
For the full report please go to newsshooter.com
Performance: autofocus and stabilisation
Generally speaking the A7S II produces less saturated and more natural colours in video and stills. This gives give much greater scope for post capture adjustment/grading.
Sony has significantly improved the A7S II’s autofocus system over the A7’s and while it’s still unlikely to tempt pro video shooters away from manual focus while shooting, it’s helpful when taking stills. You can expect a little hunting in dark interiors and outside at night, but it usually gets the subject sharp provided that you can find an area with reasonable contrast. In more average lighting conditions it’s fast and accurate. It’s also capable to tracking a moving subject in good light, but in Lock-on AF mode is often distracted by other objects in the scene so it’s better to use Flexible Spot or Expanded Flexible Spot mode and to try to keep the active AF point over the subject yourself.
• Despite the low light, the level of contrast on the woman’s face was enough for the autofocus system to get her sharp. The exposure was reduced by 1.3EV below the camera meter’s recommendation to make the shot a little darker than reality and emphasise the light on the woman’s face. Click here for a full size version.
• This image was taken at 1/15 sec to blur the movement of the cyclist, but the background is perfectly sharp thanks to the image stabilisation system (the focal length was 19mm using the Sony 16-35mm f/4 lens). Noise is also controlled well for ISO 8000. Click here for a full size version.
While you can shoot sport with it, the A7S II is unlikely to be the camera of choice for a sports photographer, especially when there are such limited long lens options. It struggled to keep up with the movement of a boxer training in a gym with flat lighting. The maximum continuous shooting speed with continuous autofocusing is also a paltry 2.5 frames per second.
• The AF system struggled to keep up with the action in the flat low light of a gym, but it was possible to get a few sharp shots. Click here for a full size version.
The built-in five axis image stabilisation system is also new for the A7S series and it works really well in video and stills mode with the appropriate lenses. When shooting video it allows you to handhold the camera and still get reasonably stable results without a tripod or monopod. Don’t expect it to make your walking or running shots look like they were shot on a Steadicam – it won’t, but it will remove the micro-jitters which are the tell tale signs of a bad handheld shot. When shooting stills we found it possible to get images that are consistently sharp at 100% when using a shutter speed of 1/15sec with Sony’s FE 90mm f/2.8 Macro G OSS lens mounted with a close subject. Many shot at slower shutter speeds also stood muster, some as slow as 1/5sec.
Unfortunately, one issue for the Alpha 7R II is also a problem with the A7S II – overheating. This is worst when shooting 4K footage to a memory card and using the EVF and image stabilisation at the same time. When it gets too hot the camera simply shuts itself down to protect itself from damage. The only real solution to this is to limit the recording times or to use an external recorder instead of the SD card.
Our experience indicates that it’s not quite as bad with the A7S II as with the A7R II, but if you’re using the EVF and stabilisation you’re likely to need to let the camera cool down after recording continuously for 30 or 40 minutes – depending upon the ambient temperature. The maximum shooting duration is actually 29 minutes 59 seconds, but if you shoot long clips in quick succession you’ll soon get close to the 30-40 minute point.
Finally, a quick word about battery life. Sony quotes a figure of 310 images when using the electronic viewfinder and measured to CIPA standards. We found this quite conservative and managed to get over 450 (raw and JPEG) images from one battery, although we were pretty careful about turning the camera off between shots. Nevertheless, if you’re shooting video you’ll find they don’t last very long and it’s a good idea to take four or five batteries if you’re going to spend a day video shooting.
Lab tests: Sony A7S II resolution
We’ve tested the resolution of the Sony A7S II using our standard test chart at ISO settings right up to the camera’s maximum of ISO 409,600. High ISO performance is one of this camera’s key selling points, so we’ve created specially extended test charts (below) to show how this camera and its rivals perform in extreme lighting conditions.
The three rival cameras we’ve chosen are:
Sony A7R II: It has more than three times as many megapixels as the A7S II, and you’d expect the trade-off to be much poorer performance at higher ISOs. But is that what happens?
Canon EOS 5D Mark III: Canon’s long-running favorite amongst pro photographers offers a great balance between stills and video quality and high-resolution/high-ISO performance.
Nikon D4S: Like the Sony A7S II, The D4S is designed to be a master of low light photography, but with 16 megapixels rather than 12, is it a better compromise for general use?
JPEG resolution analysis: It’s obvious right away that the 12 million pixel sensor of the A7S II is the major limiting factor for its resolution figures. A figure of 22 line widths/picture height is what you’d expect from a compact camera, not a full-frame professional model. The EOS 5D Mark II and Nikon D4S beat the A7S II convincingly for resolution, and the A7R II is so far ahead it’s not even in the same ballpark. But the A7S II does start to get on even terms at super-high ISOs, where its resolving power is much closer to the rest.
Raw (converted to TIFF) analysis: The pattern is repeated with raw files – in fact, the gap between the A7S II and the rest is even larger. It’s not until ISO 51,200 that it starts to edge ahead of the EOS 5D Mark III for resolution, and it never catches up with the Nikon D4S.
Lab tests: Sony A7S II dynamic range
Dynamic range is a measure of the camera’s ability to record a wide brightness range. The higher the dynamic range, the less likely you are to see burnt-out highlights or blocked-in shadows. Dynamic range is measured in EV (exposure values) and its typically highest at low ISO settings, falling off as the ISO value increases.
JPEG dynamic range analysis: The relatively low resolution of the A7S II should give it an advantage in dynamic range because the individual photosites (pixels) are larger and can in theory capture more light and hence a wider range of light values. In practice, the A7S II only starts to show an advantage at ISO 51,200, which is well outside the range of normal photography. If you do need to shoot at these ISO settings, and higher, it does have an advantage over the rest.
Raw (converted to TIFF) dynamic range analysis: Apart from an odd dip from ISO 800-1600, the A7S II is narrowly the best of this group, though the Canon 5D Mark II and Nikon D4S run it a close second.
Lab tests: Sony A7S II signal to noise ratio
The signal to noise ratio measures the amount of noise in the image compared to actual image data. The higher the number, the less noise you’ll see in the camera’s images. You’d expect the A7S II to do well here because its relatively large pixels should capture more light relative to the baseline background noise.
JPEG signal to noise ratio analysis: The A7S II is at or near the top of this group for noise levels, but its advantage is slim at best, and even then only at ISO settings of 6400 and above. Even the 42-megapixel A7R II isn’t far behind.
Raw (converted to TIFF) signal to noise ratio analysis: These results are dominated by the remarkable and unexpected performance of the EOS 5D Mark II. It beats the A7S II into third place – it’s beaten narrowly across most of the ISO range by the Nikon D4S.
The A7S is a specialised, high-sensitivity stills/video camera and according to Sony over half of the people who bought it are professionals. There’s no information about the ratio of stills to video shooters available, but our experience suggests that it’s the video element that really sold it. The A7S II is an upgrade to the A7S and it’s more attractive to videographers, with improved handling.
Sony already makes higher resolution A7-series cameras, so it’s able to target the A7S II at low light and video photography without the need to compromise it for a wider audience. The in-camera 4K recording brings it up to date – this was starting to look like a serious failing in the original model – and the faster autofocusing, 5-axis image stabilisation and better noise control are useful steps forward.
These improvements should also make the A7S II more appealing to stills photographers who need to shoot in low light and who don’t need to make prints greater than A3 in size – wedding photographers and front-line reporters are a typical examples. However, there isn’t much improvement in the image quality over the original camera’s.
With the exception of the placement of the default video activation button, which is frankly bizarre, the control arrangement of the A7S II is very good – just as it is with the A7 II and A7R II. It also more comfortable to hold and use than the original model and there’s an excellent level of customisation available.
Image quality is good for a 12Mp camera although it is more optimised for video than the A7S was.
While it struggles to keep up with fast moving subjects in low light, the autofocus system is good with stationary or slow moving subjects in very low light, provided there’s a little contrast.
The excellent noise control also makes the camera ideal for shooting handheld in the evening or indoors. However, don’t let the ISO 409,600 setting lull you into a false sense of security. When light levels are very low and ISO 409,600 is the only option, the results are pretty terrible. It’s a setting that should only be used when it’s essential to get a shot and image quality is not important. It could be a valuable option for news reporters or evidence gatherers, but there’s no guarantee that the subject will be recognisable.
The S-Log2 and 3 Gamma options are very useful, and they are easier to use because of the Gamma Display Assist that lets you see a natural image while recording very flat footage.
The A7S II is a great small camera for its target audience, though there are still a few ways in which it could be improved. Starting with the specification, the ability to record 10 or 12-bit footage would improve the quality of the colour, highlights and shadows. And some may also wish for the addition of built-in neutral density filters to save carrying lens filters.
With a relatively small pixel count and the ability to process 4K recording you might reasonably expect a faster continuous frame rate than 2.5fps for stills photography. In addition, Sony’s NP-FW50 batteries don’t last long when recording video. You’ll need to carry four or five batteries to get through a day of serious video shooting.
While the video activation button location on the original A7-series cameras was poor because it was easy to start recording by accident, the new location makes it hard to access. When you’re holding the camera it’s almost impossible to keep it absolutely steady and avoid a little wobble at the beginning and end of clips. It needs to be moved.
It would also be good to have a quicker means of AF point selection. The current set-up requires a button press and then repeated presses of the navigation buttons (or dial rolling). A dedicated direction controller would be better. In addition, the screen could do with a bigger bracket to allow it to be pulled further away from the body to make it easier to find a comfortable position when shooting from high or low angles.
We’d also like the stills and video features in the menu to be separated – any that are needed in both should appear in both. Similarly, two customisable Function menus would be helpful for anyone who shoots stills and video on their camera.
The a7S II is the best video shooting stills camera available right now. It has more professional-level features than any other and it performs amazingly well in low light. In addition, the ability to record 4K video in-camera allows users greater freedom with the ability to travel lighter and work more discretely. It’s also a great option if you need to shoot stills in low light on a regular basis but don’t need to make prints larger than A3 size (11.69 x 16.53 inches). The only serious competition comes from the 42Mp Sony Alpha 7R II, which is a very capable all-rounder.
If you shoot video occasionally and stills frequently, we’d recommend the A7R II over the A7S II and A7 II, but if video is your main concern the A7S II can’t be beaten.