Sony A7S II Field Test

Big improvements make their way to Sony's low-light champ

by Jeremy Gray | Posted 12/11/2015

Sony FE 70-200mm f/4 G OSS at 200mm, f/4, 1/250s, ISO 320
This image has been modified slightly. Click for original image.

Introduction

The Sony Alpha 7S II is Sony's new update to the original mirrorless interchangeable lens Alpha 7S camera that was released in April 2014. Although the A7S II features the same 12.2-megapixel full-frame CMOS sensor as the original, there are numerous upgrades, such as the addition of internal 4K recording, a 5-axis image stabilization system, and tweaks to the camera body itself. If you're looking for a camera that can capture excellent images in any lighting situation, the A7S II is for you.

Sony FE 24-70mm f/4 ZA OSS at 42mm, f/8, 1/6s, ISO 100
This image has been modified slightly. Black and white conversion done in post. Click for original image.

Key Features

  • 12.2-megapixel full-frame CMOS sensor
  • Uncompressed 14-bit RAW files
  • 169-point contrast detect AF
  • 5-axis image stabilization
  • Internal 4K recording
  • 0.51" OLED electronic viewfinder with 0.78x magnification

Packing a lot of features into a small space

Despite having a full-frame sensor, the A7S II is a small camera body; it weighs only 22.1 ounces (627 grams) with the battery and has dimensions of 4.7 x 2.7 x 1.5 inches (119 x 69 x 38 millimeters). Compared to other full-frame cameras I've used, the A7S II is definitely the smallest and lightest. In fact, it's even smaller than a number of cameras I've used with smaller sensors. Where other small camera bodies have sometimes come up short is with their physical controls; there is often a compromise made to ensure a compact camera body. This is not the case with the A7S II as it has numerous physical controls including dual command dials, an exposure compensation dial, and four customizable function buttons (although other buttons can be customized as well). Compared to the original A7S, the A7S II has a repositioned shutter release and command dials and a re-contoured front grip. I've not used the original A7S, but I can say that the A7S II feels very good in my hands.

The electronic viewfinder on the A7S II is upgraded as well with 0.78x magnification replacing the 0.71x one found on the original A7S. The 0.51" OLED EVF works well and with 2.35-million dots, it's very sharp. The EVF has also seen upgrades to its construction, it now has double-sided aspherical elements and Zeiss T* coating to produce a sharper display and to reduce reflection. I highly recommend changing the default settings so that the camera switches between the EVF and the rear display automatically. The eye sensor works well in many situations and it's much more convenient. It also allows you to free up a custom button that is used for switching between the EVF and rear display by default. Speaking of the rear display, it's 3" and has 1,228,800 dots, making it very crisp and bright. The display tilts, although it is not a tilt swivel display. In addition, it isn't a touchscreen, which is a disappointment. Overall, the A7S II is a very comfortable camera body to use with extensive control despite its compact camera body. Ergonomically, the controls are all positioned in easy-to-reach locations as well.

Superb sensor captures great images

Utilizing the same 12.2-megapixel full-frame CMOS sensor as the original A7S, the A7S II isn't going to blow you away with its resolving power. What it will do, however, is allow you to capture high-quality images in situations where many other cameras cannot. The A7S II boasts fantastic low light capabilities thanks to its relatively low-resolution sensor and larger per-pixel size. It's not all the same as its predecessor though, because the A7S II's BIONZ X image processor has been tweaked to provide better image quality and sharpness at higher ISOs than the original A7S.

Sony FE 24-70mm f/4 ZA OSS at 24mm, f/11, 1/10s, ISO 100
This image has been modified. Exposing for the snow, I was able to increase shadows dramatically to get this final image. Click for original image.

Sony is well-known for the dynamic range performance of their sensors and the A7S II continues that trend, providing impressive results. Thankfully, the A7S II now offers uncompressed RAW recording as well, so you'll have access to even more data than before. The uncompressed RAW files are quite a bit larger than the compressed ones, but as can be seen further below, they don't come with a big performance drop-off.

Although you'll take the best advantage of the great sensor by shooting in RAW, the A7S II captures good JPEG images too. Colors are vibrant and accurate, and tonal transitions are smooth. There are many adjustments you can make in-camera to saturation, contrast, and sharpness, so it is easy to capture images that have the look that you like. Personally, I opt for the "vivid" Creative Style in many situations because it provides JPEG files with just a bit of extra pop, although the contrast is a bit heavy for my tastes at the default setting.

Sony FE 70-200mm f/4 G OSS at 200mm, f/4, 1/250s, ISO 500
This image has been cropped. Click for original image.

In the current camera market, it's unusual to see a new full frame camera come out with a 12.2-megapixel sensor. The high ISO performance (more on that later) of the A7S II is definitely impressive, but the resolution of images does leave a bit to be desired. You can make very good prints from the A7S II, even 16 x 20 and above, but there are times when more megapixels is simply better, such as when you need to crop an image or want to make very large prints. In any case, this is likely not the camera for landscape photographers even though it has excellent image quality.

Incredible low light performance sets the new standard

Sony FE 28mm f/2, f/2, 20s, ISO 6400
This image has been resized. Click for original image.

Low light performance is where the A7S II really shines. With a native ISO range of 100-102,400 (expandable to 50-409,600), it is a low light monster. While this isn't a step up from the original A7S on paper, Sony says that there have been improvements made to mid- and high-ISO performance. Simply put, the A7S II allows you to capture great images in conditions that many other cameras cannot and this capability creates opportunities.

Sony A7S II Noise Comparison 100% Center Crops from RAW images (Click images for full-size files)
RAW files resized in Photoshop with default sharpening and noise reduction turned off
ISO 100 Full Scene
ISO 50
ISO 100
ISO 200
ISO 400
ISO 800
ISO 1600
ISO 3200
ISO 6400
ISO 12800
ISO 25600
ISO 51200
ISO 102400
ISO 204800
ISO 409600

Although capable of shooting at a staggering ISO 409,600, the native range of the A7S II tops out at 102,400. Unfortunately, ISO 102,400 isn't really usable, in my opinion, due to the high amount of noise. However, with a bit of noise reduction I was able to get usable images at up to ISO 25,600. Even RAW images at ISO 51,200 could be worked into something usable, albeit quite soft by the time the severe noise was reduced to acceptable levels. At ISO 51,200, another issue becomes visible however: red tinting along the edge of the image. You can see this in the 100% crop of a RAW image captured at ISO 51,200 below (I have performed noise reduction on the image to reduce the impact of the visible noise throughout the image).

Processed RAW file taken at ISO 51200. This is a 100% crop from the right edge of the image. You can see the red tinting along the edge.

For maintaining really high-quality RAW images, I personally wouldn't push the A7S II past ISO 6400, but even ISO 12,800 can be processed into sharp final images with acceptable levels of noise. It's really incredible to see how clean RAW files are from the A7S II at ISO 1600, an ISO speed that I regularly use for my own wildlife work and a speed that would've been pushing a digital camera past its limits not all that long ago.

With noise reduction set to normal, the A7S II produces usable JPEG images up to ISO 25,600. As with RAW images, there is red tinting that becomes distracting at ISO 51,200, but a bit of cropping would take care of that issue. JPEG images at ISO 25,600 maintain good detail and the default noise reduction does a good job of balancing noise reduction with maintaining a detailed image. The noise reduction creates a pattern that can be a bit distracting when viewing files at 100%, however, as out of focus areas take on a speckled and rough appearance that looks very digital. This effect is dramatically less at ISO 12,800 and basically gone by ISO 6400, where JPEG files just look really good.

Sony A7S II Noise Reduction Comparison: ISO 25600, 100% crops from JPEG files (click for full images)
Noise Reduction Default
Noise Reduction Low
Noise Reduction Off

The default noise reduction does a good job at preserving details while also removing a lot of noise. The 'low' setting does well too, providing slightly sharper images with minimally more visible noise. There really isn't a big difference between the normal and low settings. Noise reduction 'off' is best avoided, in my opinion, because it makes JPEG files look very noisy and in dire need of post-processing at high ISO speeds. I would shoot RAW + JPEG with the A7S II with noise reduction set to normal. It provides a very solid JPEG file at very high ISOs and you have the RAW file to work with if you need more fine-tuned noise reduction. Overall, the built-in noise reduction works really well and allows the A7S II to produce good JPEG images at very high ISO speeds.

Sony FE 28mm f/2, f/2, 15s, ISO 6400
This image has been modified slightly. Click for original image.

Perhaps in an effort to save space on the top of the camera, or maybe because you won't often need to use a flash with the high ISO capabilities of the A7S II, there is no built-in flash. When an external flash is in use, the A7S II offers your standard fare of flash options, such as flash exposure compensation and flash sync options and the maximum flash sync is 1/250s.

Actually using the camera in low light is great. Paired with a fast lens, such as the 28mm f/2, it is easy to use the camera at night because the high ISO capabilities are so good that you can get a good live view image in even the darkest conditions. The eye sensor is unsurprisingly a bit finicky in the dark, however, so I recommend turning it off (if you turned it on) when working at night. Manually focusing is a breeze at night too, with the live focus scale on the display (or EVF) providing real-time feedback.

Sony FE 28mm f/2, f/2, 13s, ISO 5000
This image has been resized. Click for original image.

Overall, the A7S II is incredible in low light. RAW performance is very good and I would not hesitate to use the A7S II up to ISO 6400 and even ISO 12,800 if the need arose. JPEG images with normal or low noise reduction look good until ISO 25,600, but ISO 51,200 and above will need considerable work to turn into usable files at any reasonably large image size. If you need to capture high-quality images in low light, you'll be hard-pressed to find a better option than the A7S II.

In the field, the A7S II is comfortable, capable and configurable

The camera body itself provides easy and quick access to many important menus. The exposure compensation dial on the top deck of the camera provides quick access to up to five stops of exposure compensation in one-third stop increments, and the customizable C1 and C2 buttons right above the dial and the C3 button just to the left of the command dial on the back of the camera are all easy to reach and can be programmed to any of a wide variety of camera settings, including ISO, focus settings, white balance, metering mode, and much more.

There are a few aspects of how the camera handles out in the field that I don't like quite as much, however. The mode dial has a locking mechanism, which means that it's slower and more difficult to rotate with one hand. Some people may consider a locking mode dial a feature, but I very rarely accidentally rotate mode dials on my cameras, so a locking mechanism feels unnecessary to me personally. Additionally, the buttons on the back of the camera, with the exception of the C3 and Menu buttons, are small and they sit relatively flush against the camera. These buttons can be difficult to press when trying to make quick settings adjustments.

Sony FE 70-200mm f/4 G OSS at 158mm, f/8, 1/160s, ISO 320
This image has been modified slightly. Click for original image.

The lack of a touchscreen becomes most apparent when using the function menu, which is accessed by pressing the Fn button above the control dial on the back of the camera. The menu itself provides access to many useful settings, such as drive mode, metering mode, focus area, focus mode, and ISO settings, but moving around the menu and changing settings using the dials can be slow and tedious.

The 1200-zone metering system in the A7S II works well and there are multi-segment, center-weighted, and spot metering modes available. For situations in which exposure compensation is necessary, the dedicated exposure compensation dial on the top deck of the camera is easily reachable while shooting. Most of the time, the camera does a good job with exposure and compensation isn't necessary. When shooting in the snow, however, exposure compensation was needed because the camera wanted to expose the snow as gray, but this is not unusual. Regarding white balance metering, I felt that the A7S II had a tendency to make images a bit too cool, but shooting RAW allowed me to address this quickly in post-processing.

Among the camera's various modes, the Sweep Panorama exposure mode lets you to create a single panoramic image from multiple images. You select from 'standard' or 'wide' panorama sizes. It's an easy to use mode, but the final image is only 1,856 pixels tall so it isn't going to provide you with the high resolution results you can could get by manually stitching your own panorama.

Sony FE 70-200mm f/4 G OSS at 200mm, f/4, 1/800s, ISO 100
This image has been modified slightly. Click for original image.

With excellent high ISO capabilities, the A7S II's auto ISO option is very useful. The A7S II includes the ability to set minimum shutter speed in addition to being able to select from a variety of settings that will change with focal length. By selecting 'fast' or 'faster' for example, when using auto ISO, the camera will use shutter speeds 1 or 2 stops faster than the camera's default shutter speed at the given focal length. By selecting 'slow' or 'slower,' shutter speeds are 1 or 2 stops slower than the default, and thus bias exposure settings toward lower ISOs.

The A7S II offers in-camera HDR shooting, as well, with both an HDR Auto mode and HDR EV (you can select from 1-6 EV in 1 EV increments). You are not able to capture HDR images when recording RAW files, however, and you can't use Auto HDR when shooting in Intelligent Auto, Superior Auto, Sweep Panorama, or Scene Selection modes.

Sony FE 24-70mm f/4 ZA OSS at 27mm, f/8, 5s, ISO 50
This image has been modified. Using auto white balance, the A7S II gave the image a purple tint. Click to see the original JPEG image.

The 5-axis image stabilization from the A7 II has been brought to the A7S II. The 5-axis image stabilization system corrects for yaw and pitch, x and y, and roll movements that can blur your image. When using one of the many E-mount lenses that have built-in image stabilization, the A7S II will complement the lens' stabilization by adding in the additional axes of stabilization support that the lens lacks so that they work together rather than on top of each other.

Sony FE 70-200mm f/4 G OSS at 200mm, f/8, 1/50s, ISO 100
This image has been resized. The A7S II's excellent image stabilization allowed me to capture a sharp image at 200mm with a shutter speed of only 1/50s. Click for original image.

Overall, the A7S II works very well in the field. The changes to the camera body pay dividends as the camera is comfortable to use for extended periods of time. And if you do plan to use the A7S II for an extended period of time, you should bring a spare battery along with you because the camera chews through its small batteries quite quickly. According to CIPA, it's rated for 370 still captures when using the LCD and 310 still captures when using the EVF. Video recording will drain the battery even quicker. Autofocus and metering performance are top-notch, and with the improvements to auto ISO capabilities, the A7S II is a very versatile camera.

Burst shooting rates disappointing & menus feel sluggish

The A7S II is not a particularly fast camera for being only 12-megapixels. In Speed Priority Continuous mode, it shoots at a maximum of 5fps. In Speed Priority Continuous mode, continuous AF is not available, so its utility depends greatly on the subject you're shooting as autofocus is locked when you capture the first frame. In Continuous shooting with full AF performance, continuous shooting speeds drop to approximately 2.5fps. Buffer depths are pretty good with the A7S II, capable of shooting approximately 64 JPEG Extra Fine, approximately 28 uncompressed RAW images, and approximately 25 JPEG Extra Fine/Uncompressed RAW images before the buffer is exhausted. The camera clears the buffer in 22, 15, and 19 seconds respectively, which is decent. The BIONZ X image processing engine does a good job overall, but the continuous shooting speeds are somewhat disappointing.

One aspect of the A7S II that surprised me is how sluggish the menu system felt at times. Trying to make adjustments occasionally felt clunky and going through image playback became slow at times.

Sony FE 24-70mm f/4 ZA OSS at 24mm, f/8, 1s, ISO 100
This image has been modified slightly. Click for original image.

Menu system in need of refinement

While the camera body itself is laid out really well, with a wide array of controls and usability features, the menu system can be frustrating to deal with, particularly when trying to change certain settings out in the field. The camera offers little in the way of explanation as to why certain menu options are grayed-out at times and forces you to scroll through menus to change settings that it should be able to change automatically.

For example, if you want to capture an HDR image while the camera is set to record RAW and JPEG images, the menu will tell you that the operation is not available. Rather than allow you to set the image quality to JPEG from there, you instead have to press OK, back out of the DRO/Auto HDR menu by pressing the 'Menu' button, scroll over four tabs to the left and then select Quality and toggle down to a JPEG quality setting. Once you've done this, you have to go back to the DRO/Auto HDR menu to change the settings. When you want to return to shooting regular images, you presumably want to record them in RAW quality as you had been before, but you now have to go back through this process again.

This may not sound like a big deal, and in many ways it isn't, but this sort of process is very common to the A7S II's menu system, and it becomes annoying and time-consuming. If Sony could put additional effort into streamlining their menu system, using their already great camera would become even more enjoyable. If there are particular options you want quick access to, such as file quality, you can assign it to a custom button, but that means that you'll likely have to make difficult decisions regarding which functions get shortcuts and which stay relegated to the clunky menu system.

Sony FE 90mm f/2.8 Macro G OSS, f/7.1, 1/100s, ISO 320
This image has been resized. Click for original image.

Internal 4K recording tops an impressive suite of video features

There are numerous improvements to the A7S II's video performance and features, including the inclusion of internal 4K recording with full pixel readout and no pixel binning (which leads to reduced moir and aliasing artifacts). Internal 4K is major convenience upgrade from the original A7S, which offer 4K video but only via HDMI. In addition, the A7S II offers clean HDMI 4K output, 1080p resolution video at up to 120fps (HFR mode), and headphone and mic inputs. For video editors, the A7S II also includes flat cinema profiles for color grading including the addition of the S-Log3 picture profile. When using these profiles, to help with achieving focus and seeing the real-time video, there is a Gamma Display Assist Function which makes the video appear more natural on the screen when recording in a flat profile.

Sony A7S II Video Sample #1
3840 x 2160, 30fps
Download Original (106.65 MB .MP4 File)

Although there are many features on the A7S II for video professionals, good performance is also there for people like me who are primarily still photographers but would like to be able to capture high-quality video from time to time. The A7S II deals with changes in lighting conditions with ease and makes seamless changes to shutter speed and aperture. It also does a great job maintaining focus, even when recording moving objects or changing composition.

Sony A7S II Video Sample #2
3840 x 2160, 30fps
Download Original (83.25MB .MP4 File)

As anticipated, recording video in low light is no problem at all for the A7S II. It records high-quality video at very high ISO settings. While the A7S II cannot record video below the native ISO 100, it has access to the high expanded ISO settings all the way up to 409,600.

The movie REC button is in a decent location, but it isn't perfect. It can be difficult to press while maintaining a good grip on the camera because the button is basically on the right side of the camera. You can assign other buttons on the camera to serve the movie REC function though, so it isn't a big deal.

Sony A7S II Video Sample #3
1920 x 1080, 120fps
Download Original (84.56 .MP4 File)

The internal 4K video recording is excellent with the A7S II, although you will need an SDXC Class-10 memory card to record in 4K resolution. Quality is very good and the rolling shutter effect is handled well. 1080p video is good as well, although it certainly isn't what most people purchasing an A7S II are interested in. The 120fps video recording at 1080p is excellent, and a nice feature to have for recording slow motion video. 4K video recording is limited to 30fps, so those looking for 60fps recording (or higher in the case of the A7S II) will need to record at 1080p resolution.

Smart Remote application offers good control and performance

Sony's Smart Remote Control application is quite good and offers a lot of control, but getting the application up and running was time consuming. I had to update the application in the A7S II, which required me to sign into my Sony Entertainment Network account. This was tedious to do on the A7S II because entering an email address and password without a touchscreen takes quite a while, after already having to enter in a wireless router password in the same way. The application store itself is very slow to load. To avoid this, you can plug your camera into your computer and run the PlayMemories Home application. For whatever reason, the application kept crashing for me, so I had to do everything on the camera itself.

Panasonic Image App Screenshots

Once the application was downloaded, setting the camera up with my iOS device was straightforward. The A7S II does have NFC, so for Android users, the process of connecting your device to the camera should be quick. With the camera connected, the application on my phone provided a lot of control and an impressive real-time feed to the phone's display. I had control over shutter speed, aperture, exposure compensation, ISO, and could use my finger to move the AF point around the screen. One strange thing was that when using the A7S II in portrait orientation, the image on the phone didn't rotate to correctly orient itself. With that said, the application is good overall and provides all of the features I expect from a smart remote application.

Sony A7S II Field Test Summary

A very impressive camera for low light shooting

What I like:

  • Improved ergonomics make the A7S II comfortable to use
  • 169-point contrast detect AF system does a good job
  • Low light performance is superb
  • Internal 4K recording produces high-quality video

What I dislike:

  • Menu system is clunky
  • Continuous autofocus performance is decent, but you can't shoot faster than 2.5fps with continuous autofocus enabled
  • Battery life is disappointing for a camera of this class
Sony FE 24-70mm f/4 ZA OSS at 24mm, f/9, 5s, ISO 50
This image has been modified slightly. Click for original image.

The Sony Alpha 7S II combines a well-designed, and compact, camera body with a 12.2-megapixel full-frame sensor that has a staggering native ISO range of 100-102,400. Add in improved autofocus relative to the original A7S and internal 4K video recording, and you have a compelling and full-featured mirrorless camera. The menu system could use refinement, and the continuous autofocus and shooting speeds leave something to be desired, but ultimately the A7S II is a great camera.

What it lacks in resolving power, the A7S II makes up for with its excellent low light capabilities and high ISO performance. For photographers needing a camera that delivers great image quality in a wide variety of situations, it'll be difficult to find a better camera than the A7S II.