> In coverage of the CIE 1931 color space the Rec. 2020 color space covers 75.8%, the digital cinema reference projector color space covers 53.6%, the Adobe RGB color space covers 52.1%, and the Rec. 709 color space covers 35.9%.
So yes, Adobe RGB covers less of the reference color space than Rec. 2020 (4k/UHD), but more than Rec. 709 (HDTV).
Yes, but of course it is debatable how relevant realizability is in practice; we have long history of using displays that have significantly smaller gamuts than whatever nominal colorspace being used.
Was rec2020 realizable in practice when it was created? I'd bet no.
UHDTV's Rec.2020 colour space actually changes the primaries, which is fantastic, but not a lot of monitors support it (yet? hopefully) and cameras seem to only support it in video mode, which hopefully is also only temporary. I'd love to shoot my photos in Rec.2020 and then view them on a 4K monitor that has the same super wide gamut!
BT2020/2100 covers 'Wide Gamut' and 'Higher luminance' (PQ / SMPTE ST:2084) - both of these in tandem are at the core of all existing HDR standards (aside from HLG which I'll save for another discussion).
Bit depth will give you a value per color channel between zero (black) and the upper bound for that bit depth (2^n - white). How the image data is encoded in those values is very much standardized for all display colourspaces (though whether the hardware is capable of displaying the full range of those values correctly is a different story).
HDR is certainly not a fad - the current crop of displays are nowhere close to being able to display the full potential of the technology yet (100% of Rec.2020 gamut @ 10,000 nits)
AndrewUnmuted - are you perhaps confusing 'true' HDR with upscaled / gamut mapped rec. 709 material? e.g. taking an existing rec. 709 master and mapping the color to a larger colourspace?
Netflix, Amazon and several other OTT providers have their original content mastered in true HDR from the get go - no post processing 'tricks'. The main limiting factor is the acquisition source, which is why Netflix have gone down the route of specifying acceptable cameras for use on their original content productions.
For most monitors, as a user you cannot know which are the true colors of the pixels of the screen and this is completely irrelevant.
What matters is which are the colors that will be reproduced on the display when you send the digital codes corresponding to pure red, green and blue, through the DisplayPort or HDMI interfaces of the monitor.
All the good monitors have a menu for the selection of the color space that will be used by DisplayPort and HDMI, and the menu will typically present a choice between sRGB and Display P3 or DCI-P3. Even when in the menu it is written DCI-P3, what is meant is Display P3, i.e. the menu changes only the primaries, without changing the white or the nonlinear transfer function.
All monitors will process the digital codes corresponding to standard color spaces to generate the appropriate values needed to command their specific pixels in order to reproduce a color as close as possible to what is specified by the standard color space.
The cheapest monitors are able to display only a color space close to Rec. 709 a.k.a. sRGB, those of medium price are normally able to display a color space close to DCI-P3 and a few very expensive monitors and many expensive TV-sets, which use either quantum dots or OLED, are able to display a larger fraction of the Rec. 2020 color space (laser projectors can display the complete Rec. 2020 color space).
Even when a monitor can display bright and saturated reds, as long as it remains in the default configuration of using sRGB over DisplayPort and HDMI, you cannot command the monitor to display those colors. For that, you have to switch the color space used by DisplayPort and HDMI to a color space with a wider color gamut.
Some monitors, typically those that are advertised to support HDR, allow the use of the Rec. 2020 color space over
DisplayPort and HDMI, but most such monitors cannot display the full Rec. 2020 color space, so the very saturated colors will either be clipped to maximum saturation or mapped to less saturated colors.
> The following color spaces offer access to larger gamuts than sRGB. The display-p3 color space offers almost twice as many colors as RGB, while Rec2020 offers almost twice as many as display-p3. That's a lot of colors!
Are there any stats on how many people have devices that support these color spaces?
You can assume that most people are using sRGB colourspace for now, but it may not be true in the coming years, especially with UHD TV being officially specified and adopting Rec. 2020 colourspace: http://www.businesswire.com/news/home/20160104006605/en/UHD-...
DCI-P3 actually is the relevant film industry standard here. No consumer displays can do Rec.2020 gamut yet, so P3 is a nice halfway step that is comparable to sRGB, unlike Adobe RGB. And it's "future-proof," because both can use the SMPTE ST-2084 EOTF.
Both the P3 and Rec.2020 gamuts are part of the UHD specification.
Note that it's fairly common to see chromaticity diagrams labelled with wavelengths around the edges, so you can check multiple sources if you want.
I didn't read the original article in sufficient depth to tell you if the researchers even know what 615nm would do, but it's not 670nm anyhow ;-).
Incidentally, the linked article also includes measured spectral responses for a few wide gamut screens, some of which have at least some response near 670nm. The most extreme on that page was the Del 3007WFP-HC LED, which peaked at 653, and has a wide peak hitting well over 700nm too (but below 650 too). A 2019 model Samsung Q80R qled TV (perhaps more common), had a peak at 632 nm, and at 670nm is about 20% as bright as at its peak.
To be fair there's a point here, which is that color spaces from sRGB to DCI-P3 to REC2020 do have quite different color/tone/brightness ranges (gamuts). Old windows boxes (and old monitors) also displayed them very differently (especially the low brightness ones). Macs were much better, and that made picking colors on them far more repeatable.
Now everyone in Windows world has standardized on sRGB and Mac on DCI-P3, but mobile is more important, where I believe it's still split sRGB Android, and DCI iPhone.
I don't know, but expect that HTML picked sRGB for their color space since this is the one people historically meant. I'd be surprised that it wasn't configurable and there weren't multiple versions, because why have a standard, when you can choose!
We won't even get into HDR, automatic brightness/eye-saver, or white point adjustment. You'ld be better off looking for a color perception scale rather than display scale, if you wanted to avoid that. Environmental lighting has big effects on perception though.
Display P3, which is what most good but still cheap monitors support, is very noticeably much bigger than sRGB, i.e. the red of Display P3 looks reasonably pure, while the red of sRGB is unacceptably washed out and yellowish.
Adobe RGB was conceived for printing better images and it is not useful on monitors because it does not correct the main defect of sRGB, which is the red.
Moreover, if I switch my Dell Display P3 monitor (U2720Q) from 30-bit color to 24-bit color, it becomes obviously worse.
So, at least in my experience, 10-bit per color component is always necessary for Display P3 in order to benefit from its improvements, and on monitors there is a very visible difference between Display P3 (or DCI P3) and sRGB.
There are a lot of red objects that you can see every day and which have a more saturated red than what can be reproduced by an sRGB monitor, e.g. clothes, flowers or even blood.
For distributing images or movies, I agree that the Rec. 2020 color space is the right choice, even if only few people have laser projectors that can reproduce the entire Rec. 2020 color space.
The few with appropriate devices can reproduce the images as distributed, while for the others it is very simple to convert the color space, unlike in the case when the images are distributed in an obsolete color space like sRGB, or even Adobe RGB, when all those with better displays are still forced to view an image with inferior quality.
The video is supposed to be encoded in Rec 2020. The panel is what it is. TV manufacturers negotiated to get a green primary close to what they could manufacture but really the panel is likely to be a little different and be color managed.
My main monitor is a Dell that is very close to Adobe RGB which is great for print work because it covers the CYMK gamut well.
I am interested in getting something better but it is not so clear to me that you can really get a Rec 2020 computer monitor other than a crazy expensive monitor from Dolby. Maybe I gotta download a bunch of monitor profiles so I can know what various monitors really support as I’ve already developed a system for simulating how channel separation works for red-cyan stereograms even on monitors I don’t have.
A better TV has been on the agenda too except somehow people keep giving me free TVs on the railing edge such as a Walmart TV which had great sound (better than many sound bars) that had the backlight burn out, then I got gifted a Samsung which sucks but is working fine in my TV nook downstairs. My main AV room doesn’t have room for anything bigger than what I’ve got unless I move everything which I don’t have a good plan for…
My understanding is that lot of the limitations of current LCD color gamuts stem from the quality of backlight used. That is why for example quantum dot technology is used to reproduce the wider rec2020 colorspace, because the spectrum of quantum dots is better suited for rgb filtering.
Although now that rec2020 is nearly an achieved goal, I do suspect that going beyond it requires more primaries as others have mentioned. Sharp experimented with a yellow primary, but that effort was fairly limited.
For oled I imagine the situation is much worse as more constraints in making the leds there.
"Rec. 2100 has the same color space as Rec. 2020."
This would have been less confusing, because the Recent. 2020 space is already being targeted by the highest end displays.
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