VESA Rolls Out Updated DisplayHDR Standard for OLED Displays: DisplayHDR True Blackby Ryan Smith on January 3, 2019 11:15 AM EST
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This morning the VESA is rolling out an update to the standard body’s DisplayHDR monitor performance standard that’s focused on expanding the specification to cover OLED displays. Dubbed DisplayHDR True Black, the new performance tiers to the DisplayHDR standard are intended for OLED and other emissive displays, laying out the levels of display performance that the association believes are appropriate for consumer HDR displays.
This update comes just over a year after the original DisplayHDR standard was launched. Intended to simplify the market for HDR displays, DisplayHDR sets a number of tiers of increasing performance, with each higher tier requiring better monitor technology and delivering a better HDR experience as a result. At the time of DisplayHDR’s launch, the VESA opted to focus on LCDs, as these displays were already in the PC market and were what the association had the most experience with. The end result was the DisplayHDR 400, 600, and 1000 standards, which covered a range of monitor designs that essentially stretched from not-very-HDR to cutting-edge full array local dimming displays.
The DisplayHDR True Black update in turn adds two more tiers to the DisplayHDR standard: DisplayHDR 400 True Black, and DisplayHDR 500 True Black. Like the tiers for LCDs, the True Black tiers are divided up based on performance; though the gap isn’t quite as big as with the LCD tiers. The end result is that displays reaching these standards, besides meeting the DisplayHDR specification’s baseline requirements, can also hit a peak brightness of 400 nits and 500 nits respectively.
The need for separate tiers for OLEDs – and other future emissive technologies like microLEDs – is rooted in the fact that HDR itself is as much (or more) about dynamic range as it is absolute maximum and minimum brightness. While LCDs can offer the necessary contrast ratios with the right backlighting technology, they are still backlit displays, meaning that they can’t quite hit black since they’re always illuminated to a degree. OLEDs, on the other hands, can hit almost perfect black levels since the pixels can simply be turned off entirely – hence the True Black moniker – which means these displays need to be measured on a different scale. Conversely, while LCDs can sustain incredible 600+ nit brightness levels over the whole screen, OLED technology can only burst to these levels for short periods of time, so the maximum brightness offered by OLED displays isn’t quite in sync either with HDR LCDs.
Overall the DisplayHDR standard covers a number of performance requirements (the VESA’s full chart is below), however as OLED displays are currently a high-end solution, DisplayHDR True Black displays are primarily competing with DisplayHDR 1000 displays. So I’ve distilled the important points to the below.
|DisplayHDR Luminance Specification Comparison|
|DHDR 1000||DHDR 500 TB||DHDR 400 TB|
|White - 10% Center Patch
|1000 nits||500 nits||400 nits|
|White - Full Screen Flash
|1000 nits||300 nits||250 nits|
|White - Full Screen Sustained
|600 nits||300 nits||250 nits|
|Black - Corner
|0.05 nits||0.0005 nits||0.0005 nits|
In short, DispayHDR True Black mandates a maximum black level performance of 0.0005 nits, 1/100th the brightness of a DisplayHDR 1000 display. While technically not 0 for practical measurement reasons (measuring nothing is surprisingly hard), in practice the standard fully expects and exploits the fact that OLED displays can turn off individual pixels to achieve perfect blacks. Conversely, the standard calls for a maximum of 500 or 400 nits respectively for a 10% patch of full white, and only 300/250 nits for the full screen. This is around half of what a DisplayHDR 1000 display can offer, which is 1000 nits for everything short of a long-duration full screen image.
The net result is that the new tiers reflect what we already know about each technology: OLEDs can get very dark, but they can’t get super bright. Meanwhile LCDs can’t hit pitch black, but they can get incredibly bright. But both can offer extensive dynamic ranges – over 20,000:1 for LCDs and 1,000,000:1 for OLEDs – allowing both to deliver the “high” part of high dynamic range. And now the standard can express these differences while requiring both display types to offer appropriate contrast ratios.
Meanwhile it’s interesting to note that the DisplayHDR True Black tiers also leverage OLEDs in one other way: response times. The standard requires a black-to-white response time of 2 frames for OLEDs, as opposed to 8 frames for LCDs. This again reflects the technology: the LED backlights in an LCD unfortunately take some time to ramp up, whereas OLED is virtually instantaneous. So DisplayHDR True Black doesn’t hold back, and certified displays need to be able to ramp up with the kind of quick response rates that the tech is capable of.
Past the specific brightness and ramp-up requirements, the other aspects of DisplayHDR True Black 500 & 400 are identical to DisplayHDR 1000/600. All of these displays need to be able to cover at least 99% of the sRGB color gamut and 90% of the DCI-P3 65 color gamut. And all internal image processing must be done with 10bpc – though 8bpc is allowed for the pixel driver. So DisplayHDR True Black displays won’t necessarily have wider color gamuts or finer steps between colors than DisplayHDR 1000 displays, rather they’ll simply operate with different ranges of luminance requirements.
DisplayHDR 500 – A Little Lighter For Laptops
Finally, tucked in along with the new True Black tiers, VESA is also rolling out DisplayHDR 500. Not to be confused with DisplayHDR 500 True Black, DisplayHDR 500 is a new tier for LCDs. Specifically, it appears to be a compromise tier aimed primarily at laptop vendors. The quality requirements are functionally identical to DisplayHDR 600, however the maximum brightness levels have been reduced to 500 nits for short durations and 320 nits for long durations, down from 600/350 respectively for DisplayHDR 600.
VESA’s announcement notes that this was done particularly to accommodate thin notebooks, where the lower tier is useful for helping to better control thermals in these laptops (a thin screen implies limited thermal mass). Though the VESA notes that like all other DisplayHDR standards, this isn’t limited to one form factor of displays, and that any display – including desktop monitors – could be DisplayHDR 500 certified if an OEM desired.
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bubblyboo - Thursday, January 3, 2019 - linkAnother scam by VESA for a pointless certification and price hike on monitors? Come back when they get true 10-bit on any specification, or make it so 600 and up don't require shitty local dimming.
JoeyJoJo123 - Thursday, January 3, 2019 - linkSomeday you'll grow into an adult.
These standards are meant to give end-consumers who aren't highly technical a comparative or baseline expectation of what they can expect the display to provide. Advanced users like you and I won't find a single certification to be enough information to base a purchase on, but the fact of the matter is that the majority of users walking into a BestBuy or Wal-Mart aren't highly technical and will walk away that day with one display or another--this certification is supposed to alleviate or provide some baseline comparative specification that's handled by an impartial party, which is already way better than displays """"claiming"""" they're capable of a 1,000,000:1 dynamic contrast ratio. Again, you and I are capable and very willing to do our own research and reading of review content before buying displays, the majority of end users don't do this and this is vastly more helpful to those consumers than the technical ones.
The DisplayHDR certifications aren't mandated for the sale of displays. If the manufacturer deems it worthy enough to test and certify a particular model of displays, they might do so. An OLED display being manufactured for sale could far exceed DisplayHDR 500 True Black's certification, but that's still at the discretion of the manufacturer if they want to get it certified or not or if the certification label is even helpful in moving/selling more display units.
That being said, VESA standards are pretty damn tame. DisplayPort is still a royalty free VESA standard, and if they're not charging royalties like HDMI or other tech standards groups, then I highly doubt that certifying a particular model of display costs that much money to a company that they need to increase the price drastically to the end user.
>Come back when they get true 10-bit on any specification
Again with this "TRUE 10-BIT" meme.
"In fact on many modern panels these FRC are very good and in practice you’d be hard pressed to spot any real difference between a 6-bit + FRC display and a true 8-bit display. Colour range is good, screens show no obvious gradation of colours, and they show no FRC artefacts or glitches in normal everyday use. Most average users would never notice the difference and so it is more important to think about the panel technology and your individual uses than get bogged down worrying about 6-bit vs. 8-bit arguments."
I trust and value TFT Central's opinions far more than some armchair tech complainer that has no better occupation than to shitpost in Anandtech article comment sections that 8-bit + FRC displays being sold as 10-bit monitors are "terrible" by any standard. At the end of the day, you'd need a fully 10-bit pipeline to see any meaningful difference, from software, to display adapter, to cabling, to display, and the sheer majority of users aren't doing any 10-bit work. 10-bit literally doesn't even matter for posting your inane comment here where sRGB (requiring 8-bit color) is the default color space of the web and for this Anandtech article you're posting in.
StevoLincolnite - Thursday, January 3, 2019 - linkI have a Kogan 6-bit+FRC and an 8-bit LG TV's in my home.
There is a difference. - Especially with black gradients... You notice it less with film/moving images with brighter contrasts.
Obviously, every-time you increase the bit depth there will be diminishing returns... 8-bit should be the minimum... With a transition to 10-bit,
HollyDOL - Friday, January 4, 2019 - linkI have 6+FRC at work and full 10-bit system at home... While not possible to compare side by side the difference is quite big (both in reproduction and also eye strain, the later might be caused also by environment factors though, light conditions at work are suboptimal). I have no 8bit at hand to test where the 'curve breaks' I would avoid 6+FRC unless the usage was occasional only (for reading emails it's more than enough).
krazyfrog - Sunday, January 6, 2019 - linkHow are you people powering these 10-bit panels? Isn't 10-bit support limited only to Quadro and Radeon Pro graphics cards?
HollyDOL - Tuesday, January 8, 2019 - linkGeForce (10xx) can do that in DirectX 11 fullscreen (likely it can do so with Dx12 as well, haven't tested).
For Adobe stuff you still need Quadro + drivers. Wasn't too happy about that investment but it allowed wife to work from home comfortably...
Absolutely no idea about situation with AMD cards though.
bubblyboo - Thursday, January 3, 2019 - linkDisplayHDR 600 and up requires local dimming or 4000:1 contrast ratio (impossible for IPS), which ends up being shitty edge lit <10 zone crap that only ends up increasing the cost of the monitor, while not providing any improvements for the end user.
Yes, it is a pointless specification when you can get a monitor certified for DisplayHDR1000 with only 32 zones of EDGE LIT dimming.
Yes the monitors end up costing far more for the end user when you force OEMs to add in useless edge lit dimming that needs to be disabled or else it screws up everything you're looking at, as well as everything needed for their own tests and Vesa's test for the certification.
Yes 10-bit matters. Just because monitors are a decade behind TVs doesn't mean the highest level of HDR on monitors should be 8-bit. 6-bit + FRC vs true 8-bit is a night and day difference unless you're blind.
Before you start telling people to "grow up" and that their comments are "inane" you should be asking yourself why you go so far to defend these companies' bullshit that only ends up harming consumers with blatantly false information.
krazyfrog - Sunday, January 6, 2019 - linkThis whole DisplayHDR business is surprisingly scammy, especially DisplayHDR 400 and 600. These are supposedly meant to help lay people (who in reality don't even know what HDR is) but only mislead by saying DisplayHDR 400 and 600 panels are true HDR when these things are barely any better than any half decent SDR monitor. Most of the HDR monitors on the market now meet these bare minimum standards because they can then pass them off as HDR. The only people these standards help are the monitor manufacturers.
JoeyJoJo123 - Monday, January 7, 2019 - link>Yes 10-bit matters.
I didn't say it didn't. HDR fundamentally needs to have that many more tones to work with to do what it needs to do. What I'm saying doesn't matter is the usage of modern FRCs in displays, which you're making to be big deal when it really isn't. 8-bit + FRC vs native 10-bit literally does not matter.
>6-bit + FRC vs true 8-bit is a night and day difference unless you're blind.
No, it's not. You're either an outright liar or the typical online commenter that can't hold back hyperbole.
>Before you start telling people to "grow up" and that their comments are "inane" you should be asking yourself why you go so far to defend these companies' bullshit.
I'm not defending anything. The certification is just that, just a certification. You need to wake up to reality that certification does not ALWAYS equal reality. An electrician can have certification to work on homes, but that's not to say they aren't lazy or that they won't get electrocuted. This is exactly why I stressed that technical users like you or I can't and rightfully don't take a look at a single certification and put SOOO MUCH WEIGHT and trust into that one certification.
You keep calling this VESA certification a scam when that's not the problem. You're the problem for putting too much weight and emphasis on a single aggregate certification which no matter which way you slice it, there will always be products that try to design the minimal possible specifications to game that certification, just as there are electricians that will do the least work possible to get certified.
leo_sk - Friday, January 4, 2019 - linkIdk. I know a couple of guys who bought hdr 400 monitors expecting to get hdr 1000 like display. Even the salesman continuously repeated that they were hdr monitors when i raised objections. I think they don't simplify it for normal end users at all. It makes it easier to loot them though