How to shoot, trim, edit, and share 4K video on iPhone 6s
The iPhone 6s and iPhone 6s Plus can shoot 4K video, or what works out to 2160p. That's four times as many pixels—twice horizontal and twice vertical—as 1080p. Not many people have TVs that can play it yet, but what makes shooting in 4K so great is that there's enough data to crop, zoom, pan, down-sample, and stabilize and still end up with great looking 1080p. 4K isn't enabled by default, though, so whether you want it raw or you want it for editing, first you have to turn it on.
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