Sony a7 IV review: Digital Photography Review

The Sony a7 IV is the fourth generation of the company’s core a7 full-frame mirrorless camera model. It’s the most advanced yet, bringing many of the improvements Sony has made in terms of autofocus and interface design since the launch of the a7 III, back in February 2018.

Key Specifications

• 33MP BSI CMOS full-frame sensor
• Up to 10 fps shooting in lossy Raw with extensive buffer
• In-body stabilization rated up to 5.5EV
• Full-width oversampled 4K from 7K, up to 30p
• 4K/60p (from 4.6K capture) in Super35 / APS-C mode
• 10-bit video or HEIF stills capture
• H.265 video, S-Cinetone color mode
• 3.69M dot OLED viewfinder
• Twin card slots (1x CFe A/UHS-II, 1x UHS-II SD)
• Full-time Bluetooth LE connection

The a7 IV sees just about every one of its specifications improved over the a7 III, from basics such as the resolution of the sensor and viewfinder to significantly increased video capture options.

The a7 IV has a recommended price of $2499, a $500 increase over the launch price of the a7 III.

Jump to:

What’s new | How it compares | Body and controls | Initial impressions | Image quality | Autofocus | Video | Conclusion | Specifications

What’s new

33MP BSI-CMOS Sensor

At the heart of the a7 IV is a new 33MP BSI-CMOS sensor. This represents a move away from the 24MP chip used by the a7 III and its immediate Panasonic and Nikon rivals. Given that BSI sensors are already widely used in the current generation of cameras, we’re not expecting huge leaps forward in image quality. A slight uptick in detail and comparable low light performance is the most likely thing we can expect, in terms of image quality.

Despite the higher resolution, the a7 IV can still shoot at 10 frames per second. However, it can only do so in the lossy compressed format if you want to shoot Raw. The a7 IV has a lossless compression option, for when you need maximum processing flexibility, but the burst rate drops to around 6 fps if you use it. Sony says the camera’s buffer depth allows over 800 Raw+JPEG images (or over 1000 JPEGs), but this is in the uncompressed Raw format, which again shoots at around 6 fps.

Our first look at the rolling shutter rates suggests this isn’t an especially fast sensor. 14-bit readout of the whole sensor for stills takes around 1/15 sec (~66ms), which is around seventeen times longer than the super-fast a1 takes to read out its sensor. This means silent shutter mode is likely to result in significant distortion with moving subjects.

Silent shutter mode is likely to result in significant distortion with moving subjects

Full-width 4K video takes around 26.5ms, which is comparable with the other models in its class. Like most of its rivals, it’s likely the camera is dropping to 12-bit readout for video mode, but the process of downsampling from 7K to 4K should reduce noise and hence prevent DR dropping to ~12EV. 60p footage has a rolling shutter rate of around 12.8ms, which is low enough to avoid distortion of all but the fastest movement.

Autofocus

In terms of autofocus, the improvements over the a7 III should be fairly significant, not so much because of the promise to focus in conditions that are one stop darker (–4EV with an F2 lens) but because that camera was one of the last Sonys that didn’t integrate Eye AF into its main AF system, and relied on a much more primitive AF tracking system. The a7 III could detect human eyes, but it couldn’t seamlessly and dependably switch between eye, face and body tracking if you set the camera to focus on a person.

The a7 IV does exactly this, and has modes that can detect and more accurately track animals, including birds, dogs and cats. For the first time, these animal detection capabilities extend to the camera’s video mode, too.

In addition, even with subjects the camera hasn’t been trained to recognize, the a7 IV uses pattern detection, subject color and brightness to help it stay focused on the subject you selected.

The a7 IV still offers a dizzying array of AF area modes (including ‘tracking’ variants of each), but you can at least disable all the ones you don’t use. The tracking versions are unavailable in video mode: instead, you tap the rear screen to select a subject for the AF to follow.

The simplicity of the system makes it difficult to convey just how effective it is. But like Canon’s latest AF system, you need only indicate to the camera what you want to focus on and it’ll use the most appropriate of its powerful AF algorithms to maximize your hit rate. Until you’ve used a system like this, or the comparable one in recent Canon cameras, it’s difficult to appreciate how powerful, reliable and simple they can be.

Video

Movie mode gets its own switch, rather than being part of the exposure mode dial. A menu option in the setup menu lets you choose which settings are carried over and which are maintained separately for stills and video.

After autofocus, the biggest area of improvement is in terms of video capability. The a7 III was the first a7 model to offer 4K capture. Its implementation was pretty good for early 2018, with oversampled 24p capture from the full width of its sensor but a crop required for 30p shooting. All footage was captured in 8-bit precision, at relatively modest bitrates.

The a7 IV moves things forward considerably, adding 10-bit capture to increase the processing flexibility of Log footage and to allow full Hybrid Log Gamma (HLG) capture for playback on HDR TVs.

It also gains the ability to shoot 4K/60p for action capture or slow-mo work, but this requires a crop to APS-C/Super 35 dimensions. This footage comes from a 4.6K region. There are also options to use H.265 compression (XAVC HS) and apply the S-Cinetone color profile.

Eye AF and the improved tracking system are now available in video mode, which should substantially increase the degree to which you can depend on autofocus staying on your chosen subject. As in stills shooting mode, the camera has been trained to recognize humans, animals and birds.

A menu option lets you decide which settings carry over from stills to video and which maintain independent values. You can choose from: Aperture, Shutter Speed, ISO, Exposure Comp, Metering Mode, White Balance, Picture Profile and Focus Mode. It’s well worth setting this up when you first start shooting with the camera, so you can just flip the Stills/Video switch when you want to jump between shooting styles.

Live streaming

A fully articulating screen can be useful for waist-level shooting, vlogging or selfies. It also allows you to monitor the camera if you’re using its streaming mode.

The a7 IV also offers the ability to live stream video over its USB connection using the audio and video standards (UVC/UAC) that are part of the USB standard. This allows a choice of HD or FullHD resolutions with FullHD available at up to 60fps. There’s also a 4K option but this only supports 15 frames per second, which gives a dreadful stop-motion look to the footage. Connection is designed to be as simple as possible, using the Imaging Edge Webcam software for Mac or PC. A connection via smartphone is also possible, though audio may not be available at resolutions above HD (720).

HEIF 10-bit stills

The a7 IV gains the ability to capture 10-bit compressed images, rather than just the 8-bit JPEGs historically offered. Unlike Canon, which only uses HEIF capture for HDR images, the Sony lets you shoot standard DR images in 10-bit, with a choice of 4:2:2 or 4:2:0 chroma sub-sampling, if you can find benefit to doing so.

The downside of this added flexibility is that you need to engage HEIF capture before you can engage the Hybrid Log Gamma (HLG) color/gamma mode, rather than having both settings change to match one another. It’s worth trying, though: images shot in HLG can show much more of the camera’s dynamic range to give a much more lifelike version of your image if viewed with an HDR-capable TV.

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How it compares

The a7 IV becomes the most expensive iteration of the a7 model yet, with a price that makes it among the most expensive of its peers. We’ve lined it up next to the similarly priced EOS R6 and the significantly cheaper Nikon Z6 II. Panasonic’s Lumix DC-S5, which we didn’t have space to include, offers a pretty similar video spec (10-bit 4K capture, including 60p from its APS-C crop) but its autofocus isn’t quite as effective. Like the Nikon, though, it’s markedly less expensive.

We’ve included the a7 III to show what the a7 IV gains over its predecessor but there’s also the smaller, less expensive a7C that shares most of its specs with the a7 III. The only major difference is that the a7 C has a slower flash sync speed and a smaller but higher resolution viewfinder. The a7C has a newer AF system than the a7 III, so its performance and usability will be a little more like that of the new camera.

This table should make clear that the a7 IV is well specced, but not to the point of standing out from its less expensive rivals. As such, it’s going to be the real-world performance of the AF system, the degree of rolling shutter in its 4K footage, and its ability to maintain its 10fps burst rate for many hundreds of images that will need to set it apart.

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Body and controls

The shoulder dial (with the toggle-lock shown in its unlocked state) controls exposure comp by default, but is now unmarked and can be set to control other functions.

The a7 IV appears to share its body with the a7S III, which offers a series of refinements over the previous a7 model. The grip is slightly deeper, the joystick on the back is improved and there’s a full-size Type A HDMI socket on the side of the camera.

A further improvement over the a7S III is the move to an unmarked lockable dial on the shoulder of the camera, meaning it can be re-purposed if you don’t shoot in a manner that requires exposure compensation.

There’s also a fully-articulating rear screen. These aren’t to everyone’s taste but allow video, vlogging and selfie shooting in a way that a tilt-out screen doesn’t.

Both of the a7 IV’s slots accept SD cards (up to UHS-II type), with the top slot also having an inner recess that accepts CFexpress Type A cards. There’s only one slow-mo video mode that requires the use of CFexpress cards: everything else can be written to V90 SD cards.

The a7 IV still offers twin card slots: both accept UHS-II SD cards with the upper one also able to take one of Sony’s small CFexpress Type A cards, which can maintain much faster write speeds than the fastest SD cards (typically 400MB/s minimum sustained write, vs 90MB/s minimum sustained write for V90 SD cards).

Improved UI

More than the ergonomic changes, we’re delighted to see the a7 IV gain the improved menus and expanded touchscreen utilization first seen in the a7S III. The menus now have their section tabs down the left-hand side of the screen, meaning you’re only ever a click or so away from being able to jump between tabs. They’re also touch sensitive, so you may not need to click or nudge anything at all.

This layout makes the menus much quicker to navigate, as do sub-section headings within each tab. The arrangement differs from previous Sony cameras but the underlying relationships between settings remain the same, so it shouldn’t take too long to familiarize yourself with the new system if you’re an existing Sony user.

Constant smartphone connection

Sony has offered Bluetooth on its cameras for many years but has used it solely for transferring location data from smartphones. The a7 IV adds a constant-connection option of the type offered by most of its rivals. This means you only have to pair the camera with your smartphone once, after which they will automatically re-establish a Bluetooth Low Energy connection, making it much quicker and simpler to transfer images to your phone.

Closable shutter

The a7 IV gains the ability to close its mechanical shutter when the camera is turned off, helping to prevent dust build-up on the sensor. Shutter blades tend to be very lightweight, which also means they can be pretty fragile, so this should be seen as dust prevention, rather than a physical protection measure.

Battery

The a7 IV uses the same NP-FZ100 battery as the a7 III and other more recent Sony cameras. It’s a usefully hefty unit that, combined with the relatively modest viewfinder res, lets the a7 IV achieve a CIPA battery life rating of 580 shots per charge using the rear screen and 520 shots per charge using the EVF.

As always, these figures are more useful for comparing cameras, rather than getting an idea of exactly how many shots you’ll get (in our experience, getting double the rated number isn’t unusual with a new battery). We tend to find a rating of over 500 shots per charge means not really having to worry about battery life in anything but the most intensive pro sports or wedding shoots.

As you might expect of a new camera, the a7 IV can be either charged or powered over its USB-C socket.

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Initial impressions

Published 22 Oct 2021

Much has changed in the eight years since the original a7 was launched: with Sony now far from alone in offering a modern full-frame mirrorless camera. Technology has made huge leaps forward, too, with autofocus, in particular, improving in terms of speed, sophistication and simplicity, to the point that no one would now suggest DSLRs retain the upper hand.

Sony’s move to bigger batteries has had a huge impact on its cameras’ usability, and its ergonomics and user interface have been radically improved with each iteration. The video features have also expanded significantly, with the fourth a7 model bringing the series back into line with its competitors.

Sony FE 35mm F1.8 | F3.5 | 1/160 sec | ISO 100 Photo: Richard Butler

What’s clearly changed, in the meantime, is the positioning. The original a7 was launched at what was then a record low price for a full-frame camera: $1700, body only. Even taking inflation into account, that’d still be a hair under $2000 in today’s money. The a7 IV’s price is a significant increase over this, and it’s notable that Sony now offers the a7C for more price or size-conscious buyers. This provision of a relatively up-to-date sister model, rather than simply lowering the prices on outdated models is a welcome change. The a7C might not have the improved menus of the a7 IV but it doesn’t feel as unrefined and clunky as the Marks I and II do, by comparison to the latest cameras.

Owners of the first two a7 models, and even some a7R series users are likely to be stunned by how far the series has come in the past few years

This move allows the a7 IV to address the needs of more dedicated enthusiasts and makes it a direct competitor to Canon’s very likable EOS R6. On paper, at least, it doesn’t go far beyond the Canon, though, so it’ll be interesting to see how they compare in real-world use. Of course, if Sony decides to continue the a7 III at a lower price, the waters get significantly muddier*. The a7 III’s autofocus is recognizably more than a generation behind the new camera, but it isn’t made to look like a work-in-progress, the way that the older models were when the Mark III arrived. The a7 III still does very well at most of the things the a7 IV does, which could undermine the attempt to push the series upmarket.

*As of Feb 2022, the a7 III is still available but the price hasn’t been reduced.

Sony seems very keen to say that the a7 IV has gained many of its improvements from the flagship a1, which we think risks implying a closer connection than actually exists. While it is not untrue that the a7 IV has some features that arrived with the a1, the new camera doesn’t have the Stacked CMOS sensor that provides the brute power underpinning the a1’s performance. In many instances, it’s fairer to point out that the a7 IV’s features are shared with the video-centric a7S III. Still not a bad thing to be able to claim, but perhaps setting more realistic expectations, in terms of how much star quality you expect to rub off on the more mass-market model.

Overall the a7 IV looks to be a very capable camera: one with much-enhanced video and more sophisticated autofocus. For newcomers, the increased price, an array of credible rivals and the high bar set by the a7 III means it’s going to have its work cut out if it’s to stand out in the way earlier a7 models did. However, owners of the first two a7 models, and even some a7R series users, are likely to be stunned by how far the series has come in the past few years.

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Image Quality

Studio test scene

Our test scene is designed to simulate a variety of textures, colors and detail types you’ll encounter in the real world. It also has two illumination modes to see the effect of different lighting conditions.

The first thing that should be apparent is that the a7 IV’s 33MP sensor can capture a lot of detail and, as we saw in our real-world samples, JPEG color that’s directly comparable with the best of its peers. The higher pixel count, combined with Sony’s JPEG sharpening makes more of the fine detail than its rivals. Moiré makes an appearance, but it’s not overwhelming, which suggests there is an anti-aliasing filter, but perhaps not an especially aggressive one.

As we’d expect, the smaller pixels mean more noise if you view the images at full pixel resolution, but this difference is all but eliminated if you look at the images scaled to the same size. Push on to the higher ISO and the noise levels start to creep up, beyond the levels of its immediate rivals, though.

Tamron 28-75mm F2.8 G2 VXD @ 75mm | ISO 1000 | 1/160 | F8.0 Processed to taste in Adobe Camera Raw Photo: Richard Butler

This additional noise can’t solely be blamed on the pixel count, though, since it’s a fraction noisier than some of its higher resolution peers. Overall this is a good, but not ground-breaking, performance with detail capture appearing to be the a7 IV’s strong suit.

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Autofocus

Autofocus is such a broad subject, with different subjects requiring different modes and different photographers preferring different approaches, that it’s almost impossible to give a comprehensive and definitive assessment of its performance. We have used the camera in a variety of situations and with different lenses but cannot cover every aspect of the camera’s performance.

Social and everyday photography

Like an increasing number of recent cameras, the a7 IV has an AF system that used machine-learning to teach it how to recognize certain types of subjects and optimize which focus point is chosen for these subjects. It builds this subject-recognition system into its main AF system and will switch between subject-aware and generic (non-recognition-based) tracking, as needed.

This means that in Wide area AF mode (where the camera chooses the subject), it’ll tend to prioritize any face it can see in the frame. But it also means that if you select one of the ‘tracking’ AF modes or tap the rear screen, you can select which person in the scene you wish to focus on.

The a7 IV makes it very easy to get the face of your chosen subject in focus. But we found a lot of the images it takes are very fractionally front-focused. It’s something that only really becomes noticeable if you use a very wide aperture and look very closely at the results, but it’s not quite as pinpoint accurate as the previous generation of Sony cameras. Sony 24-105mm F4 @ 105mm | ISO 400 | 1/250 | F4 Photo: Richard Butler

If you’ve selected a person in this way the camera will determinedly track that person, even if that person looks away. Even when we placed another person closer to the camera and nearer the middle of the frame, it continued to track our subject, even when they looked completely away and the camera could no longer see their face or eye.

Generic subject tracking also seems more ‘sticky’ and dependable than on previous generations (the AF system now uses more information about color, shape and distance to identify the subject you’d selected). And, even with the ‘Face/Eye Priority in AF’ menu setting engaged, the camera doesn’t give too much emphasis to faces: you can select a point of focus quite near an identified face without the camera assuming that you wanted to focus on it, rather than the object you selected.

However, we did find that the a7 IV can tend to very slightly front-focus when using Face/Eye detection, leaving the eye-lashes perfectly in focus but the pupil very slightly soft. This isn’t going to be an issue for everyday social photography, but if you’re trying to shoot portraits with shallow depth-of-field, the a7 IV doesn’t seem to be quite as dependably accurate as the previous generation of Sony cameras.

Autofocus Summary

Based on our experiences, Sony’s AF system is very powerful and very easy to use, giving little reason to jump between many of its (frankly overwhelming) selection of AF area modes. We found leaving the camera in AF-C with a medium-sized flexible (tracking) AF point and Face/Eye priority turned on performed very, very well in all but the most demanding of circumstances.

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Video

With the addition of 4K capture at up to 60p and 10-bit video lending greater flexibility to Log footage (and allowing full HLG capture for HDR TVs), the a7 IV is a much more powerful video camera than its predecessors.

The addition of 60p capture is another step forward for videographers who want to more accurately be able to capture fast motion or to provide some high-res slow-motion footage in a 24, 25 or 30p project. The 60p mode is only available from the Super35/APS-C region of the sensor. There’s a tiny bit of oversampling going on (it’s a 4.6K chunk of the sensor) but it’s not going to be quite as detailed as the full-width footage taken from 7K capture. The APS-C crop, along with the faster shutter speeds you’re likely to use for 60p capture are going to impose a noise penalty on the 4K/60p output, which is worth being aware of.

The a7 IV’s breathing compensation mode is useful if you’re primarily planning on shooting with high-end Sony lenses, meaning that your field of view won’t shift as the lenses focus. Even when making extreme corrections on the likes of the 50mm F1.2, the impact of cropping and rescaling the footage isn’t obvious.

More useful to more people is likely to be the ‘Focus Map’ view, which gives a simple, color-coded impression of how much depth-of-field your currently-chosen aperture is giving. Given the choice, we’d prefer the addition of either waveforms or false color displays to make it easier to optimize exposure (particularly when shooting Log footage), but it’s certainly a useful addition.

Video Stabilization

The a7 IV offers two levels of stabilization: Standard and Active. Standard uses the camera’s in-body stabilization (or lets a stabilized lens take over some kinds of correction), whereas Active crops in and adds a level of digital correction as well.

The Standard mode helps smooth out some hand motion if you’re trying to imitate a ‘locked-off’ (tripod-style shot with no movement), while Active gives something closer to a static shot.

However, despite the name, the active mode doesn’t do especially well if you try to move while the camera is recording. The a7 IV records its gyro sensor readings alongside the footage, letting you apply post-shot correction using Sony’s Catalyst software, letting you apply more stabilization in exchange for a more substantial crop, but we’ve found this to be quite a time-consuming process, that we’d probably only use in extremis.

Video Summary

The a7 IV’s video capabilities bring it back into competition with the capabilities offered by the likes of Panasonic and Canon, and its autofocus makes it easier to use. We found its image stabilization isn’t as effective at smoothing out intentional cameras movements, but overall it’s an extremely good video camera.

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Conclusion

The Sony a7 IV is the most expensive model in its series so far, but it’s also the most capable.

The a7 IV’s image quality is extremely good, with excellent levels of detail, extensive dynamic range and attractive JPEG color. However, it’s not significantly improved over its predecessor or its rivals: you’ll get more detail in low ISO situations but this small gain seems to come with slight decreases in dynamic range and high ISO noise performance. The margins are tiny but it’s hard to see a net benefit to the new chip.

Autofocus is powerful and can be very simple to use. For a majority of subjects, you can just point an AF point at your subject (or let the camera choose one), and be confident that the camera will track it and put focus in the right place. We get the sense that it’s not quite as pinpoint accurate as the previous generation of models when it comes to focusing on eyes, but it’s much quicker and easier to use.

The a7 IV is capable of excellent image quality, and its constant Bluetooth connection makes it easy to transfer images from the camera to your smartphone if you’re away from your computer. Tamron 28-75mm F2.8 G2 VXD @ 28mm | ISO 1000 | 1/30 | F8.0 Photo: Richard Butler

Video is similarly impressive, with a host of tools to support high-quality video capture. While video industry-standard features such as waveforms are absent, the a7 IV makes solo shooting easier by extending its impressive AF capabilities to video mode. Only the slightly jerky stabilization counts against what is otherwise a very powerful camera.

The a7 IV’s extensive customization and power come at the cost of complexity, though. Once you’ve explored the camera and configured it the way you want, you can ignore much of what lurks in the menus and just get out and shoot. But the ability to define virtually every behavior can be overwhelming. Even as an experienced enthusiast shooter, it was the simplicity of the AF system I appreciated much more than the extensive (excessive?) level of customization the camera offers.

In the space of eight years, the a7 series has gone from being a low-cost full-frame camera with rough edges and autofocus that lagged its DSLR peers to producing one of the most all-around capable cameras we’ve ever used. There are few photo or video activities the a7 IV can’t turn its hand to, comfortably.

Competition in this space is fierce, with Nikon and Panasonic making very capable, less expensive cameras, and Canon’s EOS R6 going toe-to-toe with the Sony in most respects. Dig deep enough, though and the ways in which the Sony stands out start to add up. It’s enough to wrest the crown from the R6, which is also enough for it to earn a Gold award.

Scoring

Scoring is relative only to the other cameras in the same category. Click here to learn about what these numbers mean.

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Sample Gallery

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