The Asus Zenfone 4 sports a dual-lens camera that happily rivals the optics of the OnePlus 5, Samsung Galaxy A5 and other mid-range smartphone cameras. We’ve fully tested this feature-packed snapper and here’s our in-depth analysis, along with photo and video samples so you can see the results for yourself.
These days you certainly don’t have to splash some serious cash to get a mobile device packing a reliable camera – as you’ll see from our best budget camera phones round-up. Many mid-range mobiles such as the OnePlus 5 and Honor 9 sport dual-lens shooters that can capture 4K resolution video and detail-packed photos that look absolutely gorgeous, with next to no expertise demanded from the user.
The Asus Zenfone 4 is one of the latest mid-tier handsets to hit the UK, rocking just such a snapper. These two lenses work independently of one another, in a similar fashion to the LG G6’s excellent camera. One is a 12-megapixel f/1.8 aperture lens, with a Sony sensor boasting large pixels to capture plenty of detail even in low-light conditions. The other is an 8-megapixel wide-angle lens, which can snap 120-degree views.
We’ve spent a lot of time with the Asus Zenfone 4 so far, so go check out our in-depth review if you want to know about the rest of this OnePlus 5 rival. Here we’ll cover everything you need to know about the Zenfone’s camera tech, including the various modes and features and what we think of the photo and video samples captured during our testing.
Check out our in-depth guide to dual lens cameras for more info on why two lenses may (or may not) be better than one. We’ve also rounded up our favourite smartphone snappers for our best mobile cameras feature.
Asus Zenfone 4 camera review: App and features
Although you can open the camera app at any time from your desktops or apps tray, Asus has also added a shortcut feature for those spontaneous snaps. If your phone is hibernating, just double-tap the Zenfone’s volume down or up button and you’ll be thrown straight in, ready to take a shot or shoot a video. This takes roughly a second or two from the button push.
The first time you boot up the Zenfone 4’s camera app, you might be a little intimidated. That’s mostly thanks to the rather large number of on-screen toggles and other virtual buttons, spread across the edges of the interface. Thankfully a few minutes of play time is all it takes to fully understand what’s going on.
All you’ll really need to crack on are the buttons along the right edge, when the Zenfone is held in portrait mode. As well as the shutter button for taking snaps, you’ll find the video button (which instantly starts a recording when tapped), alongside toggles for switching between the two rear lenses as well as the rear and front-facing cameras.
Those rear lenses work independently, so you’ll need to choose which one is best for the given situation. Thankfully that’s pretty easy. For most situations, you’ll want to stick with the more capable main lens; the wide-angle snapper is best for shooting a vista or large monument, which can’t be fully captured by the primary shooter. Flicking between the two only takes a second with the toggle button, and you can obviously check out a preview on-screen before committing to a shot.
Along the left edge of the Zenfone 4’s camera UI are a bunch of other toggles. Here you can activate the two-tone LED flash and a timer function, flick off the HDR mode (which helps out with high contrast scenes, while adding an extra bit of processing time to your shots), and change the aspect ratio. You can also turn on the Portrait mode from here, which is supposed to help your subject to stand out by blurring the background while keeping them sharply in focus; a common feature for dual-lens cameras.
Asus has also added full manual controls, if you fancy yourself as a bit of a photography pro. These are also accessed via the main camera screen. As well as a spirit level, the Pro mode offers control over the ISO levels, white balance and so on, via easy-to-use virtual dials. You can swap between the two lenses as before as well.
Flick your finger up the screen and you’ll be into the bonus camera features. This allows you to capture a GIF, shoot a timelapse or slow-motion video and so on. Alternatively, a flick down brings up a selection of filters, for changing the look of your photos.
Asus Zenfone 4 camera review: Photo quality
After a few days of camera testing, we were certainly happy with the Zenfone 4’s photo output. We rarely had to throw away a shot because it was blurred or otherwise unusable, helped along by the built-in Optical Image Stabilisation which keeps things sharp.
With a standard 16:9 aspect ratio, your photos are captured by the main lens at 9-megapixels. That’s plenty of detail to ensure your memories look crisp and attractive when you get a TV slideshow on the go. Colours are pleasingly vivid, without appearing unnatural. However, high contrast situations aren’t handled too well by the HDR feature, as too much light is often sucked in. The result is blown-out, oversaturated areas; so the likes of a bright, sunny blue sky will appear mostly white.
Moving subjects are well handled as long as they’re not too close. The shutter speed is pretty quick and you can burst shoot up to 100 photos simply by holding down the capture button.
Swap to the wide-angle camera and you’ll capture shots at 8-megapixels. The 12-degree view is well suited to tourism, particularly when you’re attempting to shoot a large, complex scene. The results are a little different to the standard lens, however. We found that less light is grabbed thanks to the smaller aperture of this lens, which means that your photos will be a little darker. On the flip side, oversaturation is much less likely.
A photo shot with the standard Zenfone 4 camera lens…
And with the wide-angle lens…
At night, the Zenfone 4 more or less holds its own. In seriously low light the HTC U11 and OnePlus 5 produce less grain, although the Zenfone isn’t far behind. Of course, you’ll want to make sure your subject is as still as possible, otherwise they’ll appear blurred.
Asus Zenfone 4 photo samples
You can see a selection of our other test photos shot on the Zenfone in the gallery below.
Asus Zenfone 4 camera review: Video quality
By default, the Zenfone 4 shoots Full HD resolution video at 30 frames-per-second. However you can bump this up to 60 frames-per-second for a super-smooth finish, or even jump to 4K Ultra HD resolution.
Our test videos came out well, with solid image and audio capture. The lens effectively deals with sudden changes in lighting and focal points, while even distant sounds are clearly recorded. Of course, you still get some issues with oversaturation on bright days.
Electronic Image Stabilisation (EIS for short) helps to keep your video judder-free when you’re moving and recording at the same time. This is more effective at the default resolution and frame rate, although still functions at 4K and does a respectable job too. There’s an occasional popping effect when moving, where the image very briefly warps, although it’s nothing too serious. We’re happy enough with the results, especially as our video doesn’t feel as mechanically produced as footage shot on the OnePlus 5.
Asus Zenfone 4 video samples
Check out our Zenfone 4 video samples below.
Asus Zenfone 4 camera review: Selfie camera
Around the front of the Zenfone 4 you’ll spy an 8-megapixel selfie camera with an f/2.0 aperture lens. This packs almost as many bonus features to tinker with as the rear camera, so can do much more than simply snap your mug.
That selfie snapper is solid for everyday use, capturing sharp, naturally coloured photos in typical conditions. You do get a fair bit of oversaturation when shooting against a bright sky however, so you’ll have to be smart with your positioning.
In dark environments you can turn on a ‘screen flash’ mode, which lights up the display in order to brighten your face. This works okay, although does tend to make us look like ghosts, thanks to our super-pale skin. Plus, the camera is actually pretty good in low light without the flash, picking up a surprising amount of detail without too much grain to ruin the results.
You can also shoot up to Full HD video, if you’re into vlogging your life.
As with the rear camera, you can shoot a GIF animation to share online. Once again you have the Portrait mode, HDR support and a timer function, although the Pro mode has been replaced with a Beautify function. This allows you to tweak everything from your face shape and skin tone to your eye size with a series of virtual dials. You’ll see the results in real time, ahead of taking the photo.
As usual, these beauty shots are more freakish than gorgeous. With the settings boosted, we resemble plastic alien sex dolls rather than human beings. Still, the skin smoother function does at least remove those wrinkles if you want to appear fresher on those social media posts.
You can also apply these beautify effects to your photos after they’ve been taken, inside of the Asus photo gallery app.