Which cameraphone is king of natural bokeh?

Outdoor scene

Our first scene is outdoors with our subject placed against a very distant background. We didn't talk about the importance of the distance of the background in our musings on the previous page, but that's because it's not going to be a variable when comparing the results between cameras for the same scene.

However, the distance of the background to the subject absolutely does matter and the further the backdrop is, the blurrier it will be. We'll observe how the level of background blur changes on the same cameras, as we move from one scene to the other.

Here's a quick refresher on the DoF values (theoretical, in mm) we obtained on the previous page.

Let's start with the telephoto cameras. After all, traditional focal lengths for portraiture can be classified as short telephoto and we have a bunch of lenses in the 70-125mm range. We have the samples arranged by the DoF numbers in the last column on the previous page - from the highest number to the lowest. In other words from images where the most should be in focus, to ones where depth of field is the most shallow and the least should be in focus. In a way, from less to most bokeh, theoretically. Having said that, it can be tough to compare focal lengths that are too far apart.

We're seeing here that the Galaxy S22 Ultra, at its 10x zoom level, does offer some subject separation and you can easily tell that the subject is the subject, but the items in the background remain fairly distinguishable and distracting. And that's with a distant background, mind you - as you'll see later, nearer backgrounds will have a dramatic effect on the achieved blur level and separation perception.

The vanilla S22 at 3x is noticeably more adept at blurring the residential building in the background that we use as our blur gauge of sorts, and we're getting some extra defocus from the Xperia 1 IV at its longer 5.2x zoom setting.

Our calculations lead us to expect a comparable level of background blur from the Xiaomi Mi 11 Ultra's 5x telephoto and the S22 Ultra's 3x unit, though a few more variables get in the way here. One is the different perspective between the two, the other is Xiaomi's less than an ideal rendition of blurred areas.

Perhaps this is a good moment to mention a topic we've deliberately tried to avoid until now, as it's not quite the main point of this article. The 'amount' of blur is only one aspect of your perception of defocused areas and often not the most important one - the 'quality' of the blur can matter a lot as well. But the thing is that 'quality' can be very subjective (even more so than our assessment of quantity here). And on top of that, perhaps it's a bit too early to start obsessing over the 'quality' of bokeh on smartphones, when we're only now starting to be getting any quantity of it in the first place.

All that is to preface that we're not loving how the Mi 11 Ultra renders its out-of-focus backgrounds even though it has plenty of blur potential. It's exhibiting distinct signs of astigmatism - the sort of double-edge artifacting that makes for a particularly nervous look. To reiterate, we're not fixating on bokeh quality just yet, but the Mi's flawed results had to be pointed out.

Outdoor scene, telephotos: Galaxy S22 Ultra 10x • Galaxy S22 3x • Xperia 1 IV 5.2x • Mi 11 Ultra 5x

The Xperia 1 IV does add some more defocus to the background at its 3.5x zoom setting compared to the 5.2x, but it's also blurrier than the Galaxy Ultra is at 3x - again, as our DoF calcs hinted. Apparently, the f/2.3 aperture is capable of overcoming the small sensor disadvantage and can almost compete with the 1/2.0" sensor units on the Axon and the Honor at the same focal length. That's explained by their dimmer lenses, though we'd still say they have an advantage over the Xperia.

Outdoor scene, telephotos: Galaxy S22 Ultra 3x • Xperia 1 IV 3.5x • Axon 40 Ultra 3.5x • Magic4 Pro 3.5x

Now, on to the primary cameras. Our calculations show that these should deliver a significant increase in background blur which should get progressively more noticeable as we move up the chart. And we'd like to think it's not just confirmation bias when we're looking at these shots and comparing.

The Galaxy S22 is showing more definition in the background than our numbers would suggest - it should be a touch blurrier than the Xperia, but the Sony's background is smoother. It could be another case of 'quality' interfering with the perception of 'quantity', though. There's a similar sort of busy-ness in the Galaxy S22 Ultra's out of focus areas so it could be a matter of Samsung's principal optical design or why not even the treatment of noise - we're seeing a lot more grain in there than in the other makers' images.

That's particularly disturbing on the S22 Ultra, which should be the second best in terms of background blur, but it's not quite delivering - we said there might be outliers.

Outdoor scene, primary cameras: Xperia 1 IV • Galaxy S22 • Magic4 Pro • Axon 40 Ultra • Galaxy S22 Ultra • Mi 11 Ultra

The Magic4 Pro does produce blurrier backgrounds than the Xperia, corroborating our numerical findings.

Blurrier still are the defocused areas of the Xiaomi Mi 11 Ultra and the ZTE Axon 40 Ultra's images. They are so different in their perspective, however. While most other 'primary' cameras in the business stand at 23mm to 26mm (we only rounded up 23mm and 24mm ones for this test), the Axon's 35mm unit is so much more flattering in its rendition of facial shapes for this specific framing that it's hardly a contest which primary camera we'd pick for people shots - the Axon wins easily.

Indeed, perspective is the other elephant in the room that we've been avoiding because it comes secondary to our premise and our goal here. But it's an unavoidable aspect of an image and just because a primary camera has better blur potential, doesn't automatically make it the go-to choice for people shots.

Frankly, the 23mm and 24mm units represented here are best avoided for such head-and-shoulders type of framing - the closeness of the subject distorts facial proportions, and that's in addition to the general awkwardness of taking pictures of someone from 30cm away.

In this sense, the Axon's 35mm main camera isn't perfect either - in terms of perspective and facial features we'd definitely prefer the look of the '3x' crowd, the 70mm to 90mm telephotos. But the Axon does combine a reasonable focal length with a bright aperture to make for one of the best options for portraits with naturally blurred backgrounds.

Indoor scene

Our indoor scene has two levels of background depth - the wall is 5m behind the subject, while the Manhattan map poster is half that - 2.5m away. That is to say, the background is way closer to the subject than what we had in the outdoor scene.

In these conditions, the Galaxy S22 Ultra's 10x tele barely shows any separation between subject and background - the map poster is sharp enough that you can read from it. The contrast in colors does allow for the model's head to stand out against the wall, but that's not what we're here for. At 3x, on the other hand, the S22 Ultra does bring some defocus to the background, a lot more than the plain S22 can muster.

Similarly, the Xperia manages to throw the background out of focus a lot better at 3.5x than it does at 5.2x.

Indoor scene, telephotos: Galaxy S22 Ultra 10x • Galaxy S22 3x • Xperia 1 IV 5.2x • Mi 11 Ultra 5x

The Mi 11 Ultra's background is looking blurrier than what our table is leading us to expect and it's not giving us that busy look - the variables in out-of-focus rendition have no end and include background distance as well.

Indeed, it's in this scene that the Honor Magic4 Pro has that distracting double-vision blur quality. The Axon's tele, meanwhile, has possibly the smoothest blur presentation in these conditions.

Indoor scene, telephotos: Galaxy S22 Ultra 3x • Xperia 1 IV 3.5x • Axon 40 Ultra 3.5x • Magic4 Pro 3.5x

On to the primary cameras. Once again, we're seeing a rather grainy rendition of out-of-focus areas by both Galaxies - noise may not be the focus of the task at hand, but it does make the blur appear more distracting. The Xperia offers the least amount of defocus though even at these short background distances there is still a decent amount of separation.

The Mi 11 Ultra and the ZTE Axon 40 Ultra offer the most background blur (with the theoretically very blur-capable Galaxy disqualified by noise), and both renditions are nicely smooth. As expected though, it's the Axon that has the best suited focal length for the task.

Indoor scene, primary cameras: Xperia 1 IV • Galaxy S22 • Magic4 Pro • Axon 40 Ultra • Galaxy S22 Ultra • Mi 11 Ultra