He's trying to say that because 400 nit isn't enough to display actual HDR contrast between pixels on an LCD, that it won't be enough on an OLED.
Not entirely. HDR is not only about contrasting deeper blacks and brighter lights, but also about bringing to life REC.2020 colour space of wide colour gamut.
In other words, higher dynamic range brings more amount of detail in an extended colour space. This brings perception of colour vibrancy. Interestingly, Asus only lists DCI-P3 coverage of 99%, but I cannot see anywhere more important wide gamur colour metric, which is Rec.2020. Funny of them...
Edit: Hardware Unboxed review states REC.2020 is 79%
The difference is LCD entire peak brightness is 400, OLED HDR400 peak is more like 1500 nit on partial coverage, because HDR content is never just a full white screen but a small percentage.
I posted the spec above, which requires 10% patch to be 400, 500 or 600 minimum. Nothing and nobody guarantees that 2% patch would ever be above 1000 unless the manufacturer tells us this in the spec. And, indeed, the spec on Asus website reads 1000 peak brightness. I suspect this is 2% patch.
ROG Swift OLED PG32UCDM gaming monitor features a 32-inch 4K QD-OLED panel with 240 Hz refresh rate and 0.03 ms (GTG) response time, along with a custom heatsink to minimize burn-in.
rog.asus.com
Of course HDR is not about full white screen. Nobody has questioned that. Devil with OLED is always in other details.
If you actually understand the serious differences in panel tech, calling OLED not true HDR is laughable. Anything except OLED at this point is crap HDR.
I have three OLED displays at home, 4K TV, 4K laptop and mobile phone. I have done my homework with OLED since 9 years.
You can get away with contrast feature at lower luminance due to per pixel benefits of OLED panel itself, but in order to bring colour vibrancy of Rec.2020 gamut, which is another important feature that HDR enhances, higher brighness is much better and visible. There is no doubt about it. It's enough if you watch a few professional TV and monitor reviews on HDTV to find out more.
I agree with you that OLED is the best display panel tech for successful implementation of HDR, but not all OLEDs are the same and there are lazy implementations of it, especially in monitor segment, whereby the public has barely entered into OLED 'era' and there is little well-established knowledge about it.
For those complaining about price, this is a 4K240 screen, with the most premium display tech we can mass produce. What you pay is what you get.
My 4K laptop has Samsung OLED display with DisplayHDR 500 certification. It is PANTONE Validated and TÜV Rheinland-certified. It's bare bones, borderline HDR, in comparison to what my TV can do with colours illuminated by HDR. The technology is simply more mature in TV segment and their display SoC are more powerful.
This Asus monitor, on the other hand, does not have Pantone and TÜV Rheinland certifications, as far as I can see. And this is not $700-800 display. Sad, but true. If monitor vendors want to charge us premium for mainstream OLED displays, the level of scrutiny by the public is more demanding and they really need to deliver on quality features and more powerful HDR capability. It's not good enough to say Oh, this is 4K/240 screen. Resolution and refresh rate are secondary here, as the primary selling point is display panel technology and the public should be informed and educated as to what to expect in this price range. Of course, this is not ProArt range, but there scrutiny is even higher.
"What you pay is what you get?" Well, we'd better know what are we getting here before paying, shall wee?
Asus advertises DolbyVision, but due to the fact that brightness is not certified as higher and Rec.2020 coverage is not listed either, the spec of this monitor does not provide information about Rec.2100 features. It looks like entry DolbyVision, which is not ideal, but it is as far as it can go with HDR400 TB certification.
Edit: Hardware Unboxed said there is no Dolby Vision out of the box. HDR10+and HLG support are not listed either, which is not good, especially now that Amazon has removed access to Dolby Vision content on Premium accounts.
Do you understand that OLED may have a 100% ABL brightness of 400 nit but a 75 ABL of 800 and a peak brightness of over 1500?
May have, well said. We will see how this pans out in testing. I am sure Tim from Hardsware Unboxed will have a closer look.
Calling OLED with perfect contrast, per pixel lighting and instant response times "not real HDR" just because it's 100% ABL is 400 nit is laughable.
Well, you can laugh as much as you wish. A legitimate question for monitors is why thos displays are still behind the quality of HDR on TVs.
VESA certifies monitors in general. HDR400 LCD is not comparable to a HDR400 OLED.
Nobody said it is.
