Camera: Bucking The Nexus Trend
LG and Google have listened to the criticism that fell on the Nexus 4s camera, and have made some changes in the Nexus 5 to try and make the device compete with other top-end smartphones. An often-praised Sony Exmor RS sensor has made it into the device, as has optical image stabilization, with the promise of a significant improvement on previous Nexus handsets.
On a more technical note, the Exmor RS sensor used is the new IMX179, which is a 1/3.2 8-megapixel unit with 1.4 µm pixels: larger than previous Exmor RS sensors, and on-par with the Nokia Lumia 925. Its combined with an f/2.4 lens with autofocus, optical image stabilization powered by a two-axis gyroscope, and an LED flash. Complementing the photography package is a 1.3-megapixel front-facing camera and 1080p video recording capabilities.
Lets start with the positives. The Nexus 5s camera is easily the best Nexus camera ever, and it can be very capable in the right conditions. Color reproduction in strong lighting is fantastic, accurate and reasonably vibrant, and photos appear sharp even though theyre only 8-megapixels large. Occasionally the automatic exposure can overexpose your shots, and white balance was infrequently dodgy, but these issues can be addressed through manual controls or a future software update.
Dynamic range from the 1/3.2 sensor is acceptable in most situations, and can be enhanced through KitKats new HDR+ mode. HDR+ is one of the better high dynamic range implementations Ive seen, correcting most cases of extreme over/underexposure and notably enhancing the quality of images. In some situations with high contrast between light and dark areas, HDR+ struggles to do anything but reduce the images exposure, but for the most part the mode is useful and functional.
You can view several full-resolution photos taken with the Nexus 5 here
Where lighting isnt so ideal, such as in heavy shadows, cloudy days or indoors, photos from the Nexus 5 are very hit or miss. I either achieved a photo that was better than I was expecting with quality on-par with strong lighting, or there were a multitude of problems. Some photos were very washed out, some had completely inaccurate white balance and some had unnecessarily high amounts of grain from an inadequate ISO.
With OIS part of the camera assembly, in many situations except the most ideal, slow shutter speeds (such as 1/8s) are used. Any shakes in your hands during photography are usually compensated for by the stabilization hardware, but it still requires a reasonably steady grip to prevent images from getting blurry. The use of slow shutter speeds means a low ISO can be used in many situations, removing grain, which in many respects is a good thing; however sometimes I needed to take two or three shots just to ensure I didnt get one that was somewhat blurry.
In low-light, the Nexus 5 performs okay, but not as great as other optically stabilized devices such as the HTC One or Nokia Lumia 925. Compared to the LG G2, which has an Exmor RS sensor with 1.12 µm pixels, an f/2.4 lens and OIS, the Nexus 5 can collect 25% more light thanks to larger 1.4 µm pixels, and on inspection produces better images. However the king of low light, the Nokia Lumia 925, has an f/2.0 lens (a half-stop larger) and a more advanced OIS system that allows 1/3s shutter speeds, effectively allowing twice the light collection at the same ISO. Its no surprise that Nokias offering trounces the Nexus 5 in the dark.
However for those doing the occasional low-light photo work, the Nexus 5s setup is better than a standard Exmor RS unit like is found on the Galaxy S4. Under automatic settings, nighttime photos taken with the Nexus 5 look brighter than real life, using ISOs around 1600. When things start getting really dark you can manually push the ISO to 6400 or so using the exposure controls, however the resultant image becomes unusably grainy, and shutter speeds below 1/6s arent used. The LED flash on the back is the usual offering found in smartphones, which means its useless over long distances and washes out the subject youre trying to capture, but remains somewhat effective where there simply isnt enough light.
The Nexus 5s/Android 4.4s camera application is underdeveloped and basic compared to the OEM-produced apps on phones such as the LG G2, Sony Xperia Z1 and HTC One. There are few manual controls to be found (exposure, white balance, flash, and a few scene selections) and a distinct lack of shooting modes other than HDR+, panorama and Photo Sphere. While the standard automatic mode is going to satisfy most users, the addition of cool burst modes, moving object erasers, composite photo modes and more can be useful and would add to the Android camera experience.
Like the Nexus 4, Galaxy Nexus and many current-day Android phones, the Nexus 5 has zero-shutter lag when taking images, allowing instant snapshots of whatevers in the virtual viewfinder. However there are several issues with the viewfinder: focusing is slow and often fails to accurate lock on exactly what you want; and the aspect ratio of the camera preview is completely wrong. For some inexplicable reason, the stock Android camera applications preview is at a near 16:9 (and unchangeable) aspect ratio but takes 4:3 images, which means what you see on the preview is not quite what you get in the final image. The same goes for the video mode, where the onscreen buttons make the preview not quite 16:9 yet videos are recorded in 16:9.
The quality of 1080p video from the Nexus 5 is essentially the same as still shots, with quick exposure changes but slow and sometimes inaccurate autofocus. OIS does a good job of smoothing stationary pans, but does little to remove shakes while walking, which is a little disappointing. The handset produces videos at 17 Mbps slightly less bitrate than other flagship devices, which hit 20 Mbps but you do get good quality albeit mono audio. It wont come as a surprise that there are few video shooting modes aside from a time lapse setting, with no HDR video or extra frame rate options.
So the Nexus 5s camera is decidedly better than the Nexus 4s, and can be quite a capable shooter in the right lighting, but its not quite at the same level as other high-end devices its competing with. Work needs to be done in camera firmware to address wildly inconsistent results in less-than-ideal conditions, focusing is often annoyingly slow, and the software itself is lackluster when placed up against other handsets. Google has taken a step in the right direction with Nexus cameras in this model for sure, just it still remains a step behind the top mobile photography players.