Xiaomi Mi A1 has the same 12MP dual-camera as seen on the Mi 5X and Mi 6. Unlike the Xiaomi's flagship, the setup on the A1 lacks OIS and has slower lenses. The regular wide-angle camera on the A1 has a 12MP sensor with 26mm f/2.2 lens and 1.25µm pixels. The 12MP telephoto sensor's specs sound familiar - 1µm pixels and 50mm f/2.6 lens - close to what Apple used for the iPhone 7 Plus telephoto cam.
The Mi A1 uses Xiaomi's proprietary camera app. Its interface is fairly simple and features toggles for HDR, Portrait Mode, and flash on the left, and 2x telephoto and the video camera on the right.
There are 17 filters available with live previews. The camera also offers a number of different shooting modes - Panorama, Timer, Audio, Straighten, Manual, Beautify, Group Shot, Tilt Shift, and Night (HHT) as well as the camera settings. The Manual mode lets you tweak ISO (100-3200), exposure time (up to 1/15s), white balance, and focus.
The Xiaomi Mi A1, just like the Mi 5X and Mi 6, snaps pictures fast, resolves a great deal of detail, and the noise levels are kept reasonably low (though a bit higher than what we saw on the Mi 6 due to the not-so-bright lens). The white balance is accurate, and we liked the lively color rendition. The dynamic range is good, but the slightly overenthusiastic metering leads to the occasional clipped highlight. There is no corner softness either, and the pictures are not oversharpened as the ones shot by the Mi 5X.
The telephoto camera also does a great job in good light and comes in handy when you need a bit of zoom. Its quality is close to the main camera's - the images have plenty of detail and the same great processing, colors, and dynamic range.
The telephoto lens has a narrower f/2.6 aperture and won't do for low-light shots. In those scenes the phone will stop using the telephoto camera and would instead switch to cropping the output of the main camera to achieve the zoomed effect. The iPhone 7 Plus does the same thing, by the way. This, of course, takes its toll on image quality, so we'd recommend against shooting at 2x zoom in low light.
The Mi A1 regular camera has good dynamic range, sure, but there are times when you'd still want to use the HDR. Here the phone does a great job brightening up the shadows without going overboard and producing unrealistic flat images.
The Mi A1 low-light shots came out rather soft. You can see what's in the picture, just don't expect much detail when you zoom in. There is a lot of noise, sometimes we also got blurry images due to the lack of stabilization, so their use is best restricted to social networks.
If you leave the automatic low-light enhancement enabled (also known as HHT - it snaps a couple of images and stacks them for better quality) - you will get much less noise in the images but most of the samples won't benefit from much more detail or higher contrast.
The closeups on the other hand greatly benefit from the HHT mode. We can show you the differences between normal and HHT low-light closeup samples with our low-light picture quality chart. We snapped the chart with both modes and here are some full-res crops.
Just like Apple, Xiaomi wants you to use the telephoto camera only in really good light and mostly for portraits. Due to the lens' narrower aperture of f/2.6, the lack of optical stabilization and its smaller sensor, the telephoto camera is probably unfit to capture good low light images.
Still, we were able to use the telephoto camera in low-light from the Manual mode - there Xiaomi offers a camera switch. Unlike the Auto mode, which produces zoomed and cropped from wide-angle samples, the low-light native telephoto pictures came out underexposed as the slower lens takes its toll. You can't compensate with shutters speed either, as Xiaomi only allows for up to 1/15s shutter speed in Manual.
The Mi A1 uses the combination of the two cameras to shoot the trendy Portrait shots. It's a process of mapping the distance to all objects of the scene and attempting to isolate the subject in front by blurring the background. This works best when you're shooting a well-lit person or an object which stands out against the backdrop. The software will get fooled by a strong backlight or a busy scene.
The Mi A1 shoots its portrait shots as fast as the iPhone 7+, but it takes longer for the camera to read the scene and apply the depth effect. The samples turned out very pleasant with mostly accurate shapes and blur effects. It's possible for the algorithm to smear an ear or some hair, though that's not an Mi A1-specific issue, but an issue of the methods themselves.
You can only capture panoramic photos with the phone in portrait orientation. You get an 180-degree field of view and the resolution comes to about 48MP (up to 4,000px tall). The image quality is great - there is plenty of fine detail, accurate colors, and no signs of bad stitching. The dynamic range is great as is the contrast.
You can also shoot telephoto panoramic shots, but those aren't as impressive - they came out soft and with limited dynamic range.
We also tested out the 5MP front-facing camera.
The images came out average in detail and a little noisy, but with high contrast, and pleasant colors. The dynamic range is about average, too.
Finally, you should check how the Xiaomi Mi A1 does against the Mi 6 and Redmi Note 4 in our Photo Compare Tool. We've pre-selected these two, but you are free to pick any other phone to compare it against.
You could also use our tool to compare the telephoto cameras of the Mi 5X, iPhone 7 Plus, and Galaxy Note8.
Video mode gives you a choice of 2160p@30fps and 1080p@30fps for common shooting with a 720p@120fps option if you want some slow-motion. There's no 1080p@60fps mode, though, and no telephoto videos either.
Anyway, the 2160p videos are captured at a bitrate of 41.6Mbps and have rock solid 30fps. The audio is stereo captured at 96KBps bitrate.
The 4K video quality is great - the resolved detail is plenty, the dynamic range is above average, the colors and contrast are very good. The noise is kept quite low, and the Mi A1 produces some really nice 4K videos. The audio quality is awful though - there are traces of compression, and you'll notice that it gets even worse with loud sound sources (loud music, crowds, cars honking, etc.).
The 1080p videos are shot at a bitrate of 20Mbps and have the same audio bitrate. The video quality in 1080p is quite different to the 4K videos though. The level of detail is very low and everything is way oversharpened. It looks like the picture was upscaled from a lower resolution and sharpened too much. This isn't the first time we've experienced this with a Xiaomi, unfortunately.
Finally, you can use our Video Compare Tool to see how the Mi A1 stacks against the Mi 6 and Mi Max 2 when it comes to video capturing.