HOW TO SHOOT 4K ON YOUR SMARTPHONE
So why would you want to record content in 4K if you don’t have a device to play it on? Read on.
HOW TO SHOOT 4K VIDEO ON YOUR SMARTPHONE
4K video recording is still fairly new, and only a handful of manufacturers have been able to add it as a feature on their premium flagship smartphones. Qualcomm’s Snapdragon 800 chip is the first SOC capable of capturing 4K footage and as such, all smartphones capable of 4K video recording are powered by either a Snapdragon 800 chip or its successor, the 801. Out of the more prominent smartphone manufacturers today, currently only Sony’s Xperia Z2, Samsung’s GALAXY Note 3 and GALAXY S5, and LG’s G Pro 2 and G3, are capable of recording 4K video.
The actual process of shooting in 4K resolution is fairly simple. While it differs from phone to phone, generally you just access the camera app, select video, and then change the resolution to 4K. It is worth noting, however, that a few smartphones limit what options are available when recording in 4K. For example, both the Samsung GALAXY S5 and Note 3 deactivate image stabilization (as well as HDR) when shooting in 4K.
The biggest limitation of recording in 4K affects every smartphone: none of them can record in 4K for more than five minutes at a time. This is due to how Qualcomm’s Snapdragon 800/801 chip processes 4K video data. Both Snapdragon 800/801 chips utilize software-based HVEC (H.265) encoding/decoding, rather than a hardware-based solution like those found in dedicated 4K video cameras. This means that all the heavy lifting while recording videos has to be done by the CPU itself, which puts it under heavy load. In turn, this leads to the processor overheating within just a few minutes of use, resulting in the phone shutting down the camera app to prevent the CPU from frying itself.
RECORDING FOR MORE THAN FIVE MINUTES WITH A SONY XPERIA Z2
If you own a Sony Xperia Z2 smartphone however, there’s actually a way to get longer 4K videos. While 4K video on Samsung and LG’s smartphones is strictly limited to five minutes, which is determined by the app itself, Sony’s camera app doesn’t have a fixed time limit, and only shuts down when the CPU temperature reaches a certain point.
With the help of some external cooling this means that you can actually go over the five minute mark. If you’re recording indoors, try setting the air con to the lowest possible setting, while outdoors a portable fan might give you a few extra minutes of recording. Of course, the easiest solution is to take advantage of the Xperia Z2’s IP58 waterproof rating and submerge the phone in a bag of ice/cold water - all except for the camera lens of course.
With over 8 million pixels compared to about 2 million of 1080p recording, 4K videos take up a lot of storage space. In our testing, across all 4K capable smartphones, on average, one second of footage took up about 11.6MB of storage space. In comparison, one second of 1080p footage used up only 2.2MB. Here’s a rough idea of how much storage space you will need to record 4K movies:
As you can see, recording in 4K will quickly use up your phone’s storage capacity. As such, it is recommended you use a high capacity microSD card to store your movies. Fortunately, Samsung, Sony and LG’s 4K capable smartphones all have microSD card slots with support up to 128GB capacity. It’s also a good idea to invest in a high-speed memory card to ensure your video is recorded smoothly without buffering and slowdowns that can occur with free or entry-level memory cards.