What are 4K, QFHD and Ultra HD resolutions?

To say that full HD, that’s 1080p resolution, has completely taken over would be a lie, and already there’s a lot of name dropping of new higher resolution standards called 4K, QFHD (Quad HD) and more recently Ultra HD.

We’ve already seen new and upcoming home cinema projectors, TV sets and computer monitors touting the new standards, while camera gear able to shoot at these resolutions are being pushed to professionals.

So what is 4K and QFHD resolution and what’s in it for you beyond a marketing scheme to make you buy new gear.

4K is rooted in digital cinema

Technically 4K stands for the horizontal resolution of the new format, which should be around 4,000 pixels across. This is different from the current crop of digital television standards, which are named based on the vertical resolution, i.e. 480p, 576p, 720p, and 1080p (i.e. 1920 x 1080). This is because 4K was created for digital cinema and as such accommodates different aspect ratios by changing the vertical resolution.

Sony, which is a major manufacturer of digital cinema projectors used in theaters world-wide defines 4K as 4096 x 2160 pixels for 8.85-megapixels, that’s four times the resolution of the previous 2K cinema standard that measures 2048 x 1080 pixels.

Here is an illustration, courtesy of Sony, demonstrating the difference between 4K, 2K and 1080p resolutions:

A number of major camera manufacturers have products supporting 4K (4096 x 2160) resolutions, like the Red One, Red Epis and Red Scarlet and more recently the Canon EOS-1D C.

But what is QFHD and Ultra HD?

QFHD stands for Quad Full High Definition and it’s exactly four times the resolution of 1080p. QFHD or Quad HD measures 3840 x 2160 pixels, and it’s a digital television format with the same widescreen 16:9 aspect ratio you are used to watching at home. QFHD is literally like combining four (two-by-two) 1080p TVs together.

This is actually the resolution that will soon be landing on TVs and computer monitors in the coming months, like the recently announced LG 84-inch Ultra Definition 3D TV, which you can see above.

Many manufacturers are marketing their QFHD products as being 4K, which has now become a catchall phrase. So if you hear about a 4K TV, the resolution would actually be 3840 x 2160, i.e. Quad HD.

Now, Ultra HD is simply a marketing term that has come up recently denoting resolutions higher than full HD (1080p). Its more likely that when you’ll be buying a new TV or projector in the next few years their resolution will be stated as 4K Ultra HD. In fact 8K would still be Ultra HD.

Above is a comparison between 720p, 1080p and QFHD and 4K resolutions; we’ve also added the QXGA resolution of the 3rd generation iPad for good measure.

Bear in mind that HDMI 1.4 already supports both QFHD and 4K 4096 x 2160.

What’s in for me?

First of all there is a marked benefit of higher resolutions for very large screens. If you’ve seen Avatar in a cinema then you’ve probably seen a 4K digital projection. For cinema there are already cameras able to capture even higher resolutions, like 6K and 8K.

But what about your living room? Well, like it or not, manufacturers will soon start pushing 4K/Quad HD resolutions to TVs and other displays. 3D has seen limited adoption, and in conjunction with Smart TVs manufacturers are hoping that 4K will be the next big thing.

As we’ve mentioned above, LG has already announced an upcoming 84-inch Quad HD TV while there are a number of home cinema projectors supporting the resolution. Sharp is also manufacturing a 32-inch QFHD (3840×2160) IGZO panel for LCD computer monitors.

For home cinema projectors and very large TVs, or computer monitors, where you sit very close to the display, these high 4K/Quad HD resolutions make sense. However for any TV smaller than 60 inches, the change from 1080p to Quad HD will no be as perceivable. In fact at normal sitting distances, for popular TV screen sizes of 50 and 47-inches the difference between 1080p and Quad HD will probably be indistinguishable to most.

Nevertheless, Quad HD and 4K is coming to TVs though content is currently non-existent, but we certainly wouldn’t recommend that you dump your current high-definition set for a 4K one, unless prices start coming down to more reasonable levels.