Sony Xperia Z5 camera tested in depth

Sony Xperia Z5 camera tested in depth

Introduction and features

The appeal of smartphone cameras is obvious – why carry around a camera specially when you’ve already got a phone in your pocket?

What we all want to know, though, is whether a smartphone can really be as good as a regular point and shoot camera, and which smartphone camera is the best of the current crop.

Apple’s built a reputation for making one of the best smartphone cameras out there, but it does not have the highest resolution – even the latest iPhone 6S has only 12 million pixels.

The camera in the Sony Xperia Z5, however, is another story. Sony says this is its best smartphone camera yet. We tested the regular Xperia Z5 but it’s the same camera in the Compact and Premium models.

Sony Xperia Z5

Sony Xperia Z5

Sony Xperia Z5

Z5 camera specs

The Z5 has a 1/2.3-inch sensor the same size as those in regular compact cameras (much smaller than a DSLR’s), and almost twice the iPhone 6S’s resolution at 23 megapixels. It also has a hybrid autofocus system covering the whole frame and capable of locking on to your subjects in just 0.3 seconds, with touch-capture control thrown in.

The Z5’s 24mm equivalent f/2.0 lens is faster and wider than the iPhone 6S’s, the sensor offers sensitivities up to ISO 12,800 and the Z5 uses the same BIONZ processing engine built into Sony’s regular digital cameras. It’s even scored the highest rating yet on DxOMark for a mobile phone (87).

Megapixels alone tell you very little, however, because high-pixel count, small-sensor cameras can quickly lose any technical resolution advantage to poor lens sharpness and aggressive image processing. And sometimes you discover limitations and restrictions in a camera you just didn’t expect.

We’ve already taken a close look at the iPhone 6S Plus in a head-to-head comparison with the old iPhone 6S. Our conclusion was that, megapixels notwithstanding, the iPhone 6S camera is the equal of any regular point and shoot camera and better than most.

So we’ve repeated the format of our previous iPhone 6S Plus vs iPhone 6 Plus test, this time pitching the Z5 against the iPhone 6S Plus in a whole series of real-world tests for resolution, noise, lens quality, exposure and color accuracy and video performance.

Sony Xperia Z5

We’re not comparing the Z5 and iPhone 6S Plus as phones, we’re comparing them as cameras. We’re also looking at this from the perspective of keen photographers wondering if a smartphone camera really can give them the quality they need.

Camera controls

If you take the Z5 camera at face value, there’s almost nothing it can’t do. It has modes for everything, from augmented reality to sweep panoramas, all revealed by a tap on the Mode button on the camera screen.

The latest Z5 update reorganizes the camera interface to make these clearer. You can now swipe between the Manual, Superior Auto, Video and Camera App modes for faster access – the Camera App mode is where you’ll find the special effects and shooting functions, including 4K video. (Oddly, the 4K option is not built into the Video mode, which offers only full HD resolution or lower.)

Sony Xperia Z5

In practice, for regular photography you’re likely to spend most of your time in the Superior Auto or Manual modes.

Superior Auto mode is much like the automatic scene selection modes on compact digital cameras. In traditional scene modes, you tap an icon to represent the kind of shot you’re taking – action, for example, or a portrait or a landscape – and the camera then chooses the right combination of settings for this subject.

Superior Auto is like the next step – the camera works out for itself what you’re photographing, and chooses the right scene settings automatically.

This is fine for novice photographers or, indeed, anyone who just needs to grab a shot in a hurry. The disadvantage is that many of the camera’s more advanced features aren’t available in this mode, such as manual white balance adjustment, focus mode, ISO setting and more.

Sony Xperia Z5

Sony Xperia Z5

Sony Xperia Z5

So if you’re keen to take control of the camera’s settings and make the most of its photographic potential, Manual mode is the place to be.

Though ‘manual’ is a rather strong word, since in reality this mode is just a little less automatic. You don’t get any more manual control than you’d expect from a regular point and shoot camera. For example, the Z5 doesn’t give you manual control over the lens aperture and shutter speed – the closest it gets is an EV (exposure value) compensation slider which makes the picture lighter or darker than the camera’s automatic setting.

The white balance control is useful, though, because it lets you take charge when the camera might get the automatic white balance setting wrong. This can happen indoors under artificial lighting, for example, or outdoors with subjects that have a single dominant color.

The iPhone 6S camera does not offer manual white balance adjustment, so the Z5 is one up in this respect, but the iPhone does have an exposure compensation slider, just like the Z5. The iPhone can also set the exposure and focus for a particular part of the scene with a single tap, or lock focus and exposure for a series of shots with a ‘long’ tap. This is a very useful feature which the Z5 lacks.

The ability to set the ISO manually on the Z5 is useful, though this option only appears if the resolution is set to 8Mp, which is both annoying and odd. It’s not the only situation where you don’t get the benefit of the full 23 megapixels, as we’ll see later.

You do need to pay attention to the settings. The Z5 sensor’s native resolution is 23 megapixels, but it defaults to just 8 megapixels – it will remember the resolution setting once you change it, though. It’s an easy thing to overlook and it could end up with a whole bunch of shots at less than half the resolution you expected.

It would be a good idea to check the image stabilizer setting to make sure this is switched on. Why would you even have an option for this? Surely you’d want the image stabilizer switched on all the time?

In fact, in the v2.0 camera update, the stabilizer option is no longer available, so we assume it’s enabled all the time. It is still possible to switch it on and off in the movie mode, though.

Interestingly, switching the stabilizer on and off doesn’t seem to make any difference to the Z5’S ISO and shutter speed choices in low light. The iPhone 6S Plus leans heavily on its stabilizer to keep shots sharp at really slow shutter speeds, which means it can delay increasing the ISO in low light for as long as possible. This does have an impact on low-light performance – the Z5 consistently used faster shutter speeds and higher ISOs in low light, which would help prevent blur but affects its ability to compete with the low-light image quality of the 6S Plus.

Sony Xperia Z5 sample image

Finally, a closer inspection of the Superior Auto mode reveals that it too offers exposure compensation and white balance adjustment – of a sort. There are brightness and color sliders that appear to do a similar thing while calling it something different.

So this isn’t a terribly easy camera to figure out. If all you want is point-and-shoot photography, then the Superior auto mode should do the job perfectly. But if you want to use the Z5 as a ‘proper’ camera and apply manual adjustments, its inconsistencies can make it confusing.

It’s worth pointing out, of course, that any comments we make about the Sony’s controls and their counterparts on the iPhone 6S Plus relate only to the default camera apps. In both cases there are third-party apps that can completely change these cameras’ features, options and controls.

Image quality

Given that this is Sony’s best smartphone camera yet, it comes with 23 million pixels and it comes from a company that’s produced some great digital cameras, you’d hope this would be good.

Well, it is and it isn’t.

The autofocus is certainly effective, and you have a choice of automatic focus point selection (you let the camera choose where to focus) or manual (you tap an object on the screen). You can also tap to shoot, making this a pretty quick and straightforward camera to use. It doesn’t feel noticeably more responsive than the iPhone 6S Plus but there’s no reason to doubt Sony’s claims about the focus performance.

Here are some sample shots:

Sony Xperia Z5 sample image

Click here for a full size version.

Sony Xperia Z5 sample image

Click here for a full size version.

Sony Xperia Z5 sample image

Click here for a full size version.

The Z5 camera produced good exposures and rich, natural colors in these three photos (above) taken at a local market.

The exposure system does a good job too. The Z5’s exposures are consistently well judged and you won’t often need the manual EV compensation control, and when you do it’s easy enough to apply. The Z5 coped particularly well with the red engine cover on Dan’s Chevrolet and a box of red chillis at the local market – these large areas of red caused a major problem for the iPhone which overexposed them and turned them a kind of blown-out orange color instead.

On the other hand, it was hard to work out what the Z5’s HDR mode achieved, if anything. None of our before and after comparisons showed any clear difference, which is in stark contrast to the effectiveness of the iPhone’s HDR mode. The iPhone’s HDR mode has its own flaws – edge artefacts around out-of-focus edges – but does a much better job of keeping detail in bright skies, for example.

Sony Xperia Z5 sample image

Sony Xperia Z5 sample image

Sony Xperia Z5 sample image

The color rendition is good too, especially with the extra control you get from the manual white balance setting in Manual mode. There are lots of occasions when the color of the lighting can distort the colors in the picture and they’re not always easy to predict. When we were photographing the produce at the local market, for example, the colors of the vegetables and crates did fool the auto white balance into odd decisions a couple of times – more so with the iPhone than the Z5, in fact.

At a casual glance, the Z5’s images look vibrant, clear and crisp. The trouble starts, sadly, if you zoom in for a closer look.

The Z5’s camera suffers, unfortunately, from the twin ills that plague cheap point and shoot compact cameras – poor lens quality, notably at the edges of the frame, and over-aggressive noise reduction.

You could argue that the average user won’t be examining images under magnification and looking for edge to edge sharpness, but then if you chose the Z5 for its camera then you certainly will. The 23-megapixel sensor is a major selling point, and you’d hope to get 23 megapixels-worth of detail.

Sony Xperia Z5 sample image

This photo shows the loss in sharpness at the edges of the picture (click here for a full size version). The blown-up sections below show how the car’s grille is rendered sharply but the leaves at the edge of the frame are just a blur.

Sony Xperia Z5 sample image

Click here for a larger version.

The edge softness and noise reduction aren’t subtle shortcomings that are easily missed. Photos will look fine on the Z5’s screen, or in tweets or Facebook posts, but the minute you open one up on your computer for a closer examination, you’re going to see the problem.

A direct comparison with shots taken on an iPhone 6S Plus at the same time is revealing. The iPhone has half the resolution in megapixels, but its detail rendition at the edge of the frame is dramatically superior.

Sony Xperia Z5 sample image

Here’s another example. The detail in the center of the picture is fine, but the detail at the edges has softened up considerably. Click here for a full size version.

Sony Xperia Z5 sample image

Note the brass post right at the bottom of the frame – this is not a depth of field issue because the iPhone version is much sharper. Click here for a larger version.

In the centre of the frame there’s much less difference between these two cameras. The Sony’s fine detail looks clean and crisp with objects that have sharp, well-defined edges (man made objects, typically) and has perhaps a slight advantage over the iPhone 6S Plus.

But with textured subjects like vegetation, fabrics and even fine patterns it’s another story. The Z5’s super-aggressive image processing smooths out anything that looks remotely like noise, with the result that finer, subtler details are routinely smudged out of existence.

When you combine this with the lens softness at the edge of the frame, it gets even worse. Detail near the edges of the picture can look as if it’s been shot through a layer of vaseline.

The answer, you might think, would be to shoot with the Z5’s 8-megapixel setting instead but, bizarrely, the edge softness and noise reduction/smudging look just as bad here too.

Sony Xperia Z5 sample image

Subjects with clear, hard edges really play to the Z5’s strengths. Click here for a full size version.

Sony Xperia Z5 sample image

Another ideal subject for the Z5’s camera, with clear outlines and good, strong colors. The focal point is in the middle of the frame and it’s shot at an angle, so you wouldn’t be expecting the edges to be sharp. Click here for a full size version.

Sony Xperia Z5 sample image

But here’s a picture that shows off the Z5’s weakness – aggressive noise reduction. The features on the faces of these comedy outfits come out fit, but the much of the fur is disappearing in a kind of smoothed-over mush. Click here for a full size version.

The Z5’s detail rendition is disappointing. It’s good for a smartphone – they’ve come a long way in a short space of time – but it’s poor by ‘proper’ camera standards and its 23 megapixels in no way make up for its poor lens and aggressive image smoothing.

Panoramas, Effects and Augmented reality

So if the Z5’s image quality is patchy, maybe it can make up for it with its huge range of effects and features?

Panoramas

The Panorama mode looks a good place to start, and it works in the same way as the iPhone’s – you pan across the scene in a single, smooth motion and the camera stitches together a single, seamless panoramic shot.

Sony Xperia Z5 sample image

But the panoramas are a disappointment. Click here for a full size version.

While the process is the same, the results are not. It turns out that the Z5 only captures in HD resolution – i.e. if you pan with the camera held horizontally you’ll get a panoramic image 1080 pixels high. Worse, the detail is soft and the joins are often jagged and clumsy. Compared to the iPhone’s panoramic mode it’s hopelessly crude. The iPhone captures at full resolution and almost always produces invisible joins – the only exception is where objects are moving across the frame as you pan, and even then you have to be unlucky to get a bad shot.

Creative effects

So maybe the Z5’s creative effects will be more impressive? They get off to a good start because they’re much more varied than the eight pseudo-retro looks you get with the built-in camera app on the iPhone 6S Plus.

Worryingly, though, the Z5 immediately offers a warning that the app may close without notice if the operating temperature becomes too high! What? It didn’t happen, but to get a warning like that at all is deeply disconcerting. You might expect something like this in some kind of experimental prototype, but not in mainstream consumer electronics.

Sony Xperia Z5 screenshot

Sony Xperia Z5 screenshot

Sony Xperia Z5 sample image

We love what the Vivid effect has done with these autumn leaves – unfortunately it’s just a 1920 x 1080 image. Click here for the actual size version.

That’s not all. In the Creative effect mode, the screen update slows to a crawl. The display is so jerky that you have to keep the Z5 still to give the display half a chance of catching up with what you’ve pointed it at, and it’s really difficult to frame moving subjects or even time the shutter release to capture them in the right position.

The effects are really nice, though, and you can adjust parameters like color saturation, depending on the effect you’ve chosen. You don’t mind the fact they’re baked into the images, unlike the reversible non-destructive filter effects on the iPhone, because they’re so attractive.

But here’s another feature with a sting in the tail. Like the Z5’s panoramic images, these Creative effects are captured at a lower resolution – 1920 x 1080 – that’s one-tenth the full resolution of the sensor (2 megapixels rather than 23).

Augmented reality and face-painting

Small children (and more than a few adults) will have a lot of fun with the augmented reality (AR) modes. We particularly enjoyed populating the street outside our fourth-floor offices with late Cretaceous vegetation, a volcano and a rampaging T-Rex. Again, the Z5 warned us it might have to shut down if the temperatures got too high, and it takes a few moments to analyse a scene before adding its prehistoric props, but it does bring a smile to your face.

Talking of faces, the Style Portrait mode is, er, interesting. It swaps to the front camera to capture selfies with a difference. It can render a portrait in black and white and add red lips, for example, which is a striking look for a female face but altogether more disturbing if the user is male. The Movie style goes further, adding eye make-up that makes you look like Cleopatra. We, uh, didn’t save those pictures.

We didn’t try all of the Sony’s creative shooting modes but it’s clear there’s a good deal of fun to be had, even if it doesn’t have an awful lot to do with regular photography.

4K video and Timeshift

We were extremely impressed by the 4K video on the iPhone 6S Plus, so would the Z5’s 4K footage stack up? Actually, it does. Our first attempts were shaky but a check of the menus revealed the cause – the stabilizer wasn’t activated.

Without an exposure lock function, it’s not possible to fix the exposure for the duration of a clip, so a moving subject against a changing background could cause problems – the exposure will change, even though the lighting on the subject is the same – but in most situations the Z5 is going to produce very good results. It’s easy to lose sight of the fact that this is a phone, and yet it’s shooting 4K video at a time it’s only just starting to appear on professional cameras.

YouTube : https://www.youtube.com/watch?v=YQDMgZqzsDc

Make sure you switch on the stabilizer. This video (above) was shot with the stabilizer off.

YouTube : https://www.youtube.com/watch?v=qvUiKjIrqYI

And now see the difference with the stabilizer switched on. The 4K video quality looks good (pity about the wind noise, though).

YouTube : https://www.youtube.com/watch?v=WzK6rK7poAY

Here’s the iPhone 6S Plus version (above).

Timeshift

The Timeshift mode (slow motion, in other words) is also impressive, but only until you look a little more closely at the results.

The resolution is the same as the iPhone 6S Plus’s at 1280 x 720 (standard HD) but the Z5 can only achieve half the frame rate – 120fps versus the iPhone’s 240fps. This means you only get a 4x speed reduction rather than the iPhone’s 8x reduction.

Even so, that’s slow enough for an attractive and impressive slow motion effect, and at first glance the video footage is sharper than the iPhone’s.

But there is a problem. In our shot of Dan’s car sweeping through autumn leaves, hard edges in the car’s body panels or details show clear imaging artifacts.

Interlacing is a way of maximising resolution with limited bandwidth by interweaving odd and even rows in the video frames. It’s an old-school fix and it’s disappointing to see it in such a cutting edge device.

It’s not just hard edges that show this interlacing effect. Small details like individual leaves on the road can be seen flickering in and out of existence between frames as they slip between the interlaced rows.

The Z5 treats Timeshift videos in the same way the iPhone handles Slow-mos, producing a movie that runs at normal speed at the start, slows down to slow motion speed in the middle and speeds back up to real time at the end. This gives a much slicker effect than a movie that’s in slow motion from start to end.

YouTube : https://www.youtube.com/watch?v=H4ahvdfAd6s

This is the Z5’s Timeshift mode in action (above). The interlacing effect is clearly visible.

However, while the iPhone 6S handles this in a straightforward way – you can change the normal/slow transition points later – the Z5 makes it a little more complicated by prompting you to choose your settings as soon as you’ve stopped recording your movie, and you have to sort this out before you can shoot another one.

Xperia Z5 vs iPhone 6S Plus

We took a wide range of shots with the Xperia Z5 to find out how it would cope with a variety of shooting conditions. And to be absolutely sure our conclusions were objective we duplicated every shot using an iPhone 6S Plus.

The Z5’s lens offers a much wider angle of view, which is very handy for interiors, landmarks and street scenes, though less good for portraits because of increased perspective distortion when you get close enough to fill the frame with your subjects.

Differences in timing and the angle of view of the two camera lenses meant that the comparison shots were rarely exactly identical, but they’re close enough to draw some very interesting conclusions.

We’ve gone through these in some detail in the preceding pages, but here we’re putting the Z5 images directly alongside the iPhone 6S Plus versions so that you can see the differences for yourselves.

Sony Xperia Z5 vs iPhone 6S Plus

The iPhone 6S Plus (left) has produced a much sharper shot than the Xperia Z5 (right). Look at the detail on the stud in the top left corner of the sign. This is where the iPhone’s better edge definition really shows. Click here for a larger version.

Sony Xperia Z5 vs iPhone 6S Plus

In low light, the iPhone 6S Plus (left) leans heavily on its image stabilizer, using slower shutter speeds to keep the ISO low. The Z5 (right) used an ISO 2x higher for the same shot, and the blow-up sections show that it’s lost any resolution advantage. Click here for a larger version.

Sony Xperia Z5 vs iPhone 6S Plus

In mixed lighting the iPhone’s color balance (left) is often a little warmer than the Z5’s (right). The iPhone has done a better job of holding on to the detail in these candles. Click here for a larger version.

Sony Xperia Z5 vs iPhone 6S Plus

This is the kind of subject that suits the Z5 (right) – large, bold details with well-defined edges. The blown-up sections show that in this instance it’s captured more detail than the iPhone 6S Plus (left). Click here for a larger version.

Sony Xperia Z5 vs iPhone 6S Plus

Low light conditions definitely favored the iPhone 6S Plus (left). Again, the Z5 used a higher ISO setting, and its combination of edge softness and heavy noise reduction mean that almost all the detail in the poster on the wall has been lost. Click here for a larger version.

Sony Xperia Z5 vs iPhone 6S Plus

The iPhone really tripped up here (left) – it overexposed this tray of red chillies so that they came out a washed-out orange. The Z5, however, (right) produced beautifully saturated colors. Click here for a larger version.

Sony Xperia Z5 vs iPhone 6S Plus

Another poor color choice by the iPhone (left), which has given these radishes an oddly warm tone. Not being able to change the white balance setting can be an issue. The Sony’s shot (right) looks great. Click here for a larger version.

Sony Xperia Z5 vs iPhone 6S Plus

The iPhone 6S Plus (left) has 12 million pixels, the Z5 (right) has 23 million – but is there really any difference in the actual level of detail captured? The Z5 photo has more pixels but the detail is more mushy. Click here for a larger version.

Sony Xperia Z5 vs iPhone 6S Plus

But as long as you don’t spend your time zooming in on the details, the Z5’s results (right) are rich and colorful. Again, the iPhone 6S Plus (left) has made a bit of pig’s ear of this red engine case, making it a kind of orange color instead. Click here for a larger version.

Sony Xperia Z5s vs iPhone 6S Plus

This is the one that really made us draw breath. Look at the iPhone 6S Plus’s rendition of the brass post at the bottom of the frame (left) compared to the Xperia Z5’s (right). This is not a focusing issue – both were focused on the same point. This is the Z5’s combination of edge softness and noise smoothing combining to create an almost textureless mess. Click here for a larger version.

Xperia Z5 camera verdict

Smartphone photography has progressed beyond simple point-and-shoot snapping. Smartphones are being used as serious tools by serious photographers. Creative smartphone photography is not just a novelty, it’s already a fully-formed movement.

This isn’t lost on Sony, which is pushing the Z5 camera’s power, performance and features for all its worth, or on Apple, which has built photography and picture sharing deep into its hardware and software ecosystem.

So we’re entitled to expect a smartphone camera to be good. Not just good ‘for a smartphone’, but good in an absolute sense.

So here’s the thing. The iPhone 6S Plus camera is modest on paper but puts in a performance which belies the numbers. The sensor has only 12 million pixels, but the lens is sharp right to the edge of the frame and details are rendered with clarity and precision, whether they’re well-defined man-made outlines (easy for any camera) or subtle, fine textures (much harder).

There are no surprises with the iPhone 6S camera. The manual controls are limited, but the focus/exposure lock options are often all you need. And there are no surprises waiting when you use the different shooting modes. Panoramas are quick and simple to shoot and captured at the sensor’s full resolution. If megapixels are your thing, an iPhone panorama is BIG. If you want to apply a photo filter, fine – the camera works just the same with no display lag and no image resampling. Again, you get a full-resolution photo, and you can even change your mind about the filter later.

The Z5 is the opposite. It has double the resolution but its lens and image processing fail to exploit that technical advantage. Where the iPhone delivers more than you might expect, the Z5 delivers less.

Sony Xperia Z5 Premium

Verdict

If you choose the Z5 for its camera you’ll find many aspects of its performance very good indeed, including the autofocus, exposure and color rendition. It’s a great camera for those who look at images as a whole and don’t study the details.

But it has three problems. The first is that the real-world detail rendition is not that good. Small sensors and high pixel counts don’t mix, and only the braver camera makers acknowledge this. The Z5 uses noise reduction processes so powerful that delicate textures and patterns are all but obliterated.

The Z5’s second problem is that the lens isn’t very good either. It’s all right in the center of the frame, but at the edges it gets very soft indeed. You wouldn’t mind that so much if this was a cheap device, but it’s not. The difference between the Sony’s lens performance and the iPhone’s is clear.

The third problem is the resolution drop you get in the Creative Effects and Panorama modes. They’re great in principle, but the results are only fit for on-screen display. We could also mention the overheating alerts (the Z5 did run pretty hot when we were using it) and the screen lag in the effects modes, but enough’s enough.

If it’s the Z5 you want rather than specifically its camera, then you’re probably not going to be disappointed, but if you’re looking for the smartphone with the best camera then this – sadly – isn’t it.



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