Last weekend the airshow was in town, and it was a perfect opportunity for me to test out the 4K video recording mode on my new 6S+. Now, my intention was not to keep any 4K recordings of the event, but instead to edit in 4K in iMovie then export to 1080p. Why would I do this? Mainly for the ability to zoom in post-production without excessive loss of resolution. The result came out pretty great. Check it out (make sure to set the quality to 1080): I over-used the digital zoom a bit on the first scene and it's a tad blurry, but keep watching. I'm pretty happy with how most of the shots came out. I'm not sure if any of you have tried to shoot video of an airshow using an iPhone before, but normally you end up with tiny specks in the sky. The distance of the aircraft is a problem with a fixed lens camera. And digital zooming while recording at 1080 degrades the image way too quickly. But by recording in 4K, there are a lot more pixels to work with. It is very easy in iMovie to select a clip and apply a zoom to it. Jump to 3:07 in the video to see a place where I started off without zoom, then split the clip and applied zoom to the second half of the clip where the planes approached each other. This shooting approach even has an advantage over a proper video camera with a zoom lens. Shooting fast-moving planes while zoomed in is HARD. You very easily lose track of the planes, and everything is shakier. But in 4K, you can keep the camera at a wider angle and not have to track the planes so carefully. Then in post-production, position the zoom just where you need it. Much better. One other thing that's VERY apparent in this example is how great the Optical Image Stabilization (OIS) on the 6S+ is. I was not using a tripod and I did not apply any software stabilization on the phone or in YouTube. This is straight from shooting to iMovie to rendering. The OIS performance on this phone is jaw-dropping. Also, the performance of the 6S+ and iMovie while editing 4K video is equally jaw-dropping. There was essentially no lag at all. While editing 4K! How the heck did Apple manage that in a smartphone?? Pros use uber-expensive desktop rigs to edit footage like this.