Last week I wrote a post about how Nikon really needs to jump on the 4k bandwagon. I got a few comments that basically said; "Why do you care about 4k? nobody even owns a 4k TV at this point." They were right, 4k TVs aren't very popular, but I have no interest in producing 4k videos right now. I want to shoot 4k footage to enhance my 1080p videos.
Sharper 1080P footage
You may think that HD footage is a universal standard and anything shot in "HD" will look ultra sharp but that isn't true. "High Definition" footage can mean 720i/p or 1080i/p footage. Most HD cameras today will shoot in 1080p (the highest level of HD footage) but there is no regulation at all on a camera's bit-rate.
To save money on processors and memory buffers, cheaper cameras typically output HD footage at a relatively low bit-rate (megabits per second). This causes your footage to look soft, pixelated, and muddy.
In the example below I've taken a Jpeg image using the Nikon D750 and have shrunk it down to 1080p and I've also taken a still from a video clip of the exact same scene. I've then cropped in so that you can see the pixels at 100%. The D750's video footage is actually quite good compared to other DSLRs but the image below shows you just how far 1080p video footage still has to improve.
4k footage, named because it has 4000 pixels horizontally (4096x2160), is approximately the size of 4 standard 1080p (1920x1080p) video files. Shrinking down 4k footage to be 1080p is a night and day difference in detail and quality. Down-sampling can also help cut down on noise and grain making the footage appear to be cleaner as well.
In theory it is possible for a high end 1080p camera to film higher quality footage than a cheap 4k camera, but in my experience most 4k cameras are significantly sharper than 1080p cameras.
Shooting 4k video footage to get a sharper 1080p final export is the ultimate reason to shoot 4k but I've got 5 other uses for 4k that make it even more useful.
Stabilizing Footage in Post
While Hollywood has a team of people and an unlimited budget to produce flawless camera moves, I don't have that luxury and sometimes I'm forced to shoot hand-held. Even if I am standing perfectly still with a optically stabilized lens on my camera, you're going to be able to see camera shake. If I have to start walking, the footage becomes unusable.
Video effects like Premiere's "Warp Stabilizer" can save shaky footage, but it requires that the footage be "zoomed in" to work. If your 1080p footage is already soft, cropping in another 20% will make it unusable.
Shooting in 4k will give you enough pixels to play with so that effects like video stabilization will have no discernible effect on your finished video.
Cropping Footage In Post
You've heard photographers say for the last 10 years: "I like having more megapixels because it gives me more cropping options." Now that same luxury is available for film makers. When we were filming our landscape photography tutorial we used a Dji Phantom 2 with a Gorpo 4 Silver at 2.7k (2.7k is larger than 1080p but smaller than 4k).
Since I didn't have a vision downlink system I had to fly the drone and guess what I was filming. Back in post I was able to crop the footage to be the best composition without losing any quality in the final 1080p export.
Chances are, you've never considered cropping your video footage because it wasn't an option. Once you've experienced the flexibility of recomposing a shot after you've shot it, you'll never want to go back.
Perfect Pans and Zooms
Have you ever tried to film a perfectly smooth pan with a video camera? It's almost impossible. Have you ever tried to film a perfectly smooth zoom with a manual lens? It's literally impossible.
If you shoot 4k, small pans and zooms have never been easier. Simply zoom out, grab a few seconds of your scene and then add a pan or a zoom once you get back to the computer.
Adding these movements to your video in post will actually look better than anything you can do in the field and because 4k gives you so many extra pixels to work with, your finished product will look flawless.
Shooting A and B Roll Shots At The Same Time
If you've ever filmed an interview with someone you know that you will need to run a minimum of 2 cameras. A 5 minute video might have around 20-100 cuts in it and to mask each of them, you will need to jump from camera to camera to avoid the dreaded "jump cut." Shooting 4k and exporting in 1080p gives you a lot of room to play and basically can give you 2 or even 3 different looking shots (wide, medium, and tight).
For many of our videos we end up setting 2 cameras in almost an identical position, one shooting wide and the other shooting tight. One 4k camera could easily replace this 2 camera setup.
4k Footage Is Good Enough To Pull Still Frames
Most 1080p video footage looks so low res that still frames really aren't even good enough for web use. If it's not good enough for a website, you certainly wouldn't consider printing a still frame from a standard HD video camera but 4k is changing that.
Not only is most 4k footage good enough to replace standard still images on the web, but many shooters are starting to realize that 4k still frames are actually good enough to print. To put this into perspective, a 1080 video contains 2 million pixels where a single frame of 4k video contains 8.8 million pixels.
Check out our video where we compare a Hasselblad file to a still frame pulled from a very outdated Red Epic. Back in 2012 when we filmed this we were all really impressed with the Epic but today the Red Dragon puts the Epic to shame.
4k is far from being a common household format. Even though it is easy to go out and buy a 4k TV, you will have a very hard time finding footage to play on it. Luckily 1080p footage has so much room to improve. You shouldn't run out and buy a 4k video camera because you want to see your footage in 4k but, you should consider filming in 4k simply to enhance your standard, HD footage. Unlike 3D, it's pretty obvious that 4k is the future and even if it never becomes universally adopted it will help improve your videos today no matter what format you are working in.