Why 4k? Why not call it 2160p?

[zachska87]

For years, the standard of "HD" has been 1920x1080, referred to as 1080p, with the vertical axis pixel count being the normal way to reference a screen. This was the same with 720p. Why, with these new screens being a resolution of 4096x2160 are they being referred to as "4k" screens instead of 2160p or even "2K?" Why did the reference axis change? I just wondered if anyone knew...especially since the number of horizontal pixels is not consistent across "4K" screens, while the vertical pixels are.

[TheExodu5]

It's purely a marketting thing. Instead of people thinking "oh, 2160p is just twice that of 1080p", they'll be thinking "4k is four times 1080p". It's also a shorter, catchier name.

[Chief Blur Buster]

It was a pre-existing name (4K) used for hollywood digital masters that existed long before 4K displays really existed.

4K is an easier, more marketable name too, than a number "2160p".

[SS4]

Also 2160p is more than double 1080p, because its 2D and both the width and height are increased meaning the screen resolution is actually 4 times higher

[zachska87]

It was a pre-existing name (4K) used for hollywood digital masters that existed long before 4K displays really existed.

4K is an easier, more marketable name too, than a number "2160p".

That makes sense, I wondered if there was some pre-existing thing I didn't know about...it just seemed like a really weird change otherwise (other than simply being more marketable). Thanks!!

[SisterBob]

What's funny is that "Ultra High Definition" was chosen to be the official terminology about a year ago by the Consumer Electronics Association with the express goal of replacing the use of 4K. But 4K had already caught on and I haven't seen "UHD" pop up very often or at all since.

[spacediver]

2160p is actually a better term. As Mark said, 4k is a term that is traditionally reserved for digital cinema. In 4k digital cinema, the term 4k defines its horizontal resolution (4096 pixels). Depending on the aspect ratio, which differs from movie to movie, the vertical resolution varies, but the horizontal resolution remains the same. Thus, the image is defined by the horizontal resolution and the aspect ratio.

In consumer end displays, the image is defined by the vertical resolution (720p, 1080p), as the aspect ratio is fixed.

So one argument for using 2160p is to maintain consistency in nomenclature.

Another more insidious issue is this:

In consumer end "4k" displays, the horizontal resolution is 3840 pixels. Now this introduces a potential problem, as content is produced with a horizontal resolution of 4096, but has to be delivered at 3840. Care has to be taken to choose the appropriate scaling algorithms and/or cropping decisions.

If the term 4k is used for both consumer displays and digital cinema post production, then there is the risk that the conflation of terminology may lead to a failure to transfer appropriately.

[SS4]

Unless they come out with an even larger aspect ratio than 16:9 just like how they pretty much killed 16:10 . . . And hopefully they might increase the res on monitor a bit, we don,t see 1050 on 22 " much anymore they are 1080 instead.
I don't care much for his UHD 4K crap coz besides for movie its almost pointless in games where your framerate will plummet down. Imagine 3d vision or worse, eyefinity at those resolutions . . . . yeah, they better come out with GPU farm to replace SLI/xfire lol

[spacediver]

well depending on how UHD is implemented, they may allow for some of the enhancements to trickle down to 1080p and 720p. For example, increased bit depth, color gamut, and frame rates. Either way, if the consumer display industry reacts well to UHD, we could see a proliferation of computer monitors, video cards, and applications that support higher color bit depth.

And this is a good thing

[spacediver]

just noticed something interesting. 4096 looks like 40% with the default font settings