Presented by DPReview.com
4K: What you need to know
 

What is 4K?

If you've been shopping for a camera recently you'll probably have seen the term '4K video' plastered on shop displays and even written on the labels stuck on the front of products. 4K is a video specification that literally just means '4,000'. It gets its name from the approximately 4,000 pixels of width of the footage.

Technology doesn't stand still for long and there's a new video standard in town: 4K.

The name 4K is used to describe a couple different, though very similar, standards. The form you're most likely encounter is Ultra High Definition or UHD, the new standard for 4K television. 4K video is poised to become the new benchmark for both recording and watching video and it brings a whole host of benefits, right away.

Get more clarity in your video

The images below represent the difference in details between various video resolutions. Video captured using a Panasonic LUMIX DMC-LX100.

Standard Definition (480p)

Digital cameras circa 2000 and TVs in the late 90s / early 2000s. Can't make out much, right?

High Definition / HD (720p)

Some modern digital cameras offer slow motion video at this resolution.

Full HD (1080p)

Most modern digital cameras record at this resolution.

4K

Few cameras offer 4K video recording but when you can, the footage is incredibly sharp compared to 1080p. Read on for more details why.

What does it mean for video shooters?

If you shoot HD video, should you upgrade your camera to a 4K-capable model, even though many people still don't have a 4K TV? The obvious reason to make the switch to 4K is to future-proof your work.

Where we're going, we don't need 1080p!

Consumers may not demand 4K content today, but at some point they will, and if history is any guide this will probably happen soon. Just imagine if you had continued to shoot in standard definition up until the moment that everyone finally had an HD television. Who would want to watch that crunchy, mushy low-resolution content today? As a content creator you're always better off getting ahead of the curve.

However, even if you don't need (or want) to create 4K content yet, there are number of huge benefits to adopting a 4K workflow now.

If you shoot HD video, should you upgrade your camera to a 4K-capable model? The obvious reason to make the switch to 4K is to future-proof your work.

Where we're going, we don't need 1080p!

Consumers may not demand 4K content today, but at some point they will, and if history is any guide this will probably happen soon. Just imagine if you had continued to shoot in standard definition up until the moment that everyone finally had an HD television. Who would want to watch that crunchy, mushy low-resolution content today? As a content creator you're always better off getting ahead of the curve.

However, even if you don't need (or want) to create 4K content yet, there are number of huge benefits to adopting a 4K workflow now.

Better 1080 HD Footage

Shooting 4K will make your HD video look better. Most HD cameras today capture great quality 1080p video, but when you start with 4K source material and downscale it to HD resolution the picture will look even better, thanks to effectively oversampling each pixel by a factor of four. In addition to sharper, crisper images, color data is better and easier to grade, and common video artifacts such as moiré are significantly reduced or eliminated thanks to the higher resolution original capture.

Crop / Zoom / Pan

4K capture also makes it possible to take advantage of editing techniques that would be impossible - or at least not easy - with HD footage. Need to crop in tight on something you shot? No problem - you can crop by up to 4x on 4K footage and still maintain full HD video resolution. Similarly, all those extra pixels allow you to zoom in, out, or even pan across an image while maintaining HD resolution.

Still Images from Video

Have you ever shot a video for a client, only to have them come back later and tell you they need a still image for an advertisement or marketing campaign? 4K to the rescue. Although it only has twice as many horizontal lines as HD video, 4K footage has four times the total resolution of HD. While you can eek out a 2MP still image from standard HD video, that's not enough to be useful for anything much beyond online use. 4K, however, gives you the ability to extract an ~8MP image from your video. That's enough for a nice sized print or even an ad in a magazine.

Image Stabilization

All those extra pixels can also come in handy for stabilizing your footage. Most non-linear editors, such as Adobe Premiere Pro and Apple Final Cut Pro X, include image stabilization algorithms that do a remarkably good job of artificially stabilizing handheld footage and making it look like you shot with a Steadicam. Unfortunately, this process decreases the resolution of the footage by strategically scaling, rotating and cropping your footage frame-by-frame to counteract camera shake. If you're starting with HD source material this means that the resulting video may be noticeably less sharp, as you're cropping out pixels. If you're working from 4K, however, you have a significant amount of extra pixels to play with. Stabilize away!

Green Screen

Shooting against a green screen is a common video technique that allows editors to combine a foreground subject, such as a person, with a different background. This process, called chroma keying, is made much easier with more pixels.If you have 4x the density of pixels in your source footage the key will be better.

4K Video for Photographers

How could a video mode ever be useful for stills photography? Well, think of it as a way of shooting 24, 25 or 30 eight megapixel images per second and you might start to understand the appeal. Whether it's a child's brief smile after blowing out their birthday candles or a match-winning goal being scored, this shooting speed can help make sure you capture the perfect moment.

Panasonic's 4K Photo mode lets you choose the right still image directly from the 4K footage.
Image provided by Panasonic.

Many current cameras let you extract frames from video footage in playback mode, and some let you hit the shutter button during recording, to mark out which frames you want to grab.

Panasonic's 4K Photo mode lets you choose which image to save.
Image provided by Panasonic.

Several Panasonic cameras take this a little further with a dedicated '4K Photo' mode that lets you shoot footage in more conventional aspect ratios, rather than being locked to the panoramic format of most video. Some cameras also include clever functions to help you capture the moment, such as a pre-record mode that constantly records footage, then saves the 30 frames before and after you hit the shutter.

It's entirely possible to pull great images from 4K video from any camera, but if you're shooting video with the explicit intent of getting stills, your images will benefit from some fine-tuning of settings and technique. As always in photography, time spent experimenting is not time wasted.

More keepers shooting at 30fps

4K video at 30fps: In 1 second of 4K footage you get 30 photos. Fast-moving racecars are tough subjects to frame properly, though with so many photos to choose from, you're more likely to get a keeper.
Shot with a Panasonic LUMIX DMC-G7.

Missed opportunities with slower bursts

Burst modes on most cameras are 5-8fps: Most consumer digital cameras are only able to shoot 5-8 pictures in a second, much slower than 4K. You might get one or two good photo with enough practice and timing, but multiple photos in the same sequence is near impossible.
Shot with a Panasonic LUMIX DMC-G7.

4K Challenges

As great as 4K is, the extra resolution might mean that you'll need to upgrade parts of, or potentially all of, your production pipeline. This might include memory cards, displays, hard drives, computers, and possibly even lenses. Below, we'll take a look at how to prepare for a 4K world.

How do I prepare for 4K?

Manufacturers of both consumer and professional electronics are scrambling to add 4K video to their products, but with more pixels comes an awful lot more data to push around.

File storage

4K footage takes up a lot more space than full HD - up to four times more, in fact. A single minute of video on some prosumer 4K-capable video cameras can weigh in at more than one gigabyte.

In order to keep up with all that data, you'll need fast memory cards, capable of at least 30MB per second write speed (which corresponds to the U3 rating on SD cards). This should allow recording at quality settings up to around 200mbps.

Panasonic memory cards that support 4K recording.

Memory cards aren't quite as expensive as they once were, but high-speed cards still represent a significant investment, and one that needs to be factored in to the cost of a new 4K-capable camera.

Storage to record 1 hour of video on different cameras

Storing all that data for editing also means a fast, high-capacity hard drive. You'll need at least a 7200rpm conventional hard drive on a USB 3.0 or faster connection, and as much storage as you can afford. Solid State Drives (SSDs) are significantly faster than spinning-disk drives but they're much more expensive per GB of storage.

Do I need a new computer?

It depends. In the same way as 4K video requires a lot of space to physically store, it also requires a lot more processing power to handle it when it comes to editing the footage.

As always when looking at computer performance, the main things to consider are processor speed, the graphics card, how much RAM is installed, and the type and capacity of hard drive.

You'll soon know if your computer isn't up to the task of editing 4K video. But even if you're having issues, you may be able to get by editing proxy footage (offline) as opposed to the actual original footage (online).

Apple's Mac Pro desktop computer is more than enough to handle 4K editing.

Display requirements

It is possible to shoot, edit and publish a 4K video project without ever viewing the footage on a 4K monitor, but we wouldn't recommend it.

If you're looking for a single monitor workflow, expect to spend at least $500 and keep an eye out for the 'IPS' designation. IPS panels are superior when it comes to color accuracy at different viewing angles. If you already have a color-accurate monitor, you can go with an additional, more budget-oriented 4K monitor for cutting footage together, and continue doing color grading on the older monitor.

Editing lower resolution footage then exporting to 4K is one option.
Image provided by Panasonic.

Workflow and Sharing

Editing 4K footage doesn't just require a powerful computer, you'll also need specialized video editing software.

There are plenty of video editing suites out there, and 4K support is becoming more common even for inexpensive options like Apple's iMovie. But for the best results we'd recommend more full-featured software like Adobe's Premiere Pro, or Apple Final Cut Pro X. Just be aware that different cameras shoot video in different ways, and different video editing software interacts with these file formats in different ways too, so you should do some research to find which software will work best with your footage.

Let's say you've produced your prize-winning 4K content and are ready to share it with the world. Great! But before you do that, here are some things to think about.

If you want or need to share your work in full-resolution 4K you can easily share the files directly via your prefered online cloud storage service, but depending on your Internet connection speed, upload and download times will probably be very lengthy. 4K video is still not very well-supported by online video hosting services, but Vimeo allows you to make 4K footage available for download and YouTube offers 4K streaming (albeit highly compressed).

Finally, consider: do you even need to output in 4K? As we said in the introduction to this article, HD video is great, and it's fine for most purposes. There are some huge advantages to shooting and editing 4K, but when it comes to sharing your work, 4K might be overkill. If you output as HD, file sizes will be significantly smaller for one thing, and you won't need a UHD screen to view the footage at its full resolution. Even if you output HD though, you should always save a 'futureproof' full-resolution 4K version to disk.

Adobe Premiere Pro CC by Adobe.
Available on both Windows and OS X.

Final Cut Pro X by Apple.
Available only on OS X.

Service Streams 4K Can upload 4K to
YouTube
Vimeo
Pro accounts allow 4K videos to be downloaded

Let's say you've produced your prize-winning 4K content and are ready to share it with the world. Great! But before you do that, here are some things to think about.

If you want or need to share your work in full-resolution 4K you can easily share the files directly via your prefered online cloud storage service, but depending on your Internet connection speed, upload and download times will probably be very lengthy. 4K video is still not very well-supported by online video hosting services, but Vimeo allows you to make 4K footage available for download and YouTube offers 4K streaming (albeit highly compressed).

Service Streams 4K Can upload 4K to
YouTube
Vimeo
Pro accounts allow 4K videos to be downloaded

Finally, consider: do you even need to output in 4K? As we said in the introduction to this article, HD video is great, and it's fine for most purposes. There are some huge advantages to shooting and editing 4K, but when it comes to sharing your work, 4K might be overkill. If you output as HD, file sizes will be significantly smaller for one thing, and you won't need a UHD screen to view the footage at its full resolution. Even if you output HD though, you should always save a 'futureproof' full-resolution 4K version to disk.