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Home Theater Geeks 535: All About BT.2020
00:39:46
The Ultimate Range of Colors
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- [00:00]
Jeff Urich
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- [00:28]
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- [00:30]
Scott Wilkinson
In this episode of Home Theater Geeks, I talk with my friend Jeff Urich about BT 2020. Watch out, it's gonna get geeky. Stay tuned.
- [00:44]
Jeff Urich
Podcasts you love from people you trust. This is.
- [01:01]
Scott Wilkinson
Hey there, Scott Wilkinson here, the home theater geek. In this episode, I'm going to talk with my friend Jeff Urich, the VP of marketing at Nanisys, makers of quantum dots and suppliers to most of the display manufacturers in the world. Hey Jeff, welcome back to the show.
- [01:21]
Jeff Urich
Hey Scott, great to be back.
- [01:23]
Scott Wilkinson
Always glad to have you here. So today we are going to talk about BT 2020, which is the ultimate range of colors that an RGB based display can reproduce. And it's going to get pretty geeky. So strap in everybody.
- [01:44]
Jeff Urich
Very geeky indeed. Yes. Yeah.
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Scott Wilkinson
Now, Jeff, you attended the Society for Information display display week 2026 conference in LA where the inventor of BT 2020, Kenichiro Masaoka, presented the information that you're going to now share with us.
- [02:09]
Jeff Urich
Yeah, exactly. Dr. Masaoka, one of the principal inventors of BT 2020 color gamut. And there was a panel discussion about BT 2020 with him and books from the Hollywood side from some TV brands. It's really interesting back and forth discussion, but he got to kick it off with this 10 or 15 minute presentation on BT 2020. What inspired him to create it and sort of what it's all about. And he allowed me to share the slides with your audience today. So I will be doing my best to live up to his sort of level of geekery. But, you know.
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Scott Wilkinson
Yeah, he is, he is a serious geek. No doubt about that.
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Jeff Urich
Yep.
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Scott Wilkinson
But we're glad to have you here to help us understand this. I don't want to call it a gamut because that implies a specific luminance.
- [03:05]
Jeff Urich
Right, right, that's, that's right. It's, it's actually, well, yeah, it's actually a chromaticity gamut the way that it's specified in XY chromaticity coordinates.
- [03:19]
Scott Wilkinson
And what's really good news is that you've got the PowerPoint that he presented there to show us.
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Jeff Urich
Yeah, actually. Do you want me to open that up and start?
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Scott Wilkinson
Sure, right now.
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Jeff Urich
Okay, let's see.
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Scott Wilkinson
Let's take a look.
- [03:31]
Jeff Urich
The name of the panel for Display week was the BT 2020 standard. The benefits and costs of enhancing display color capability. This is really what's interesting for me to see as someone who's been following wide color gamut and display technology for a long time. And we saw, as we talked about on the last episode, a lot of interest about BT 2020 at CES. And that really continued through to Display Week. And so it's really interesting to see a panel discussion around this standard and what it's all about. And so you can see here, Masoka Stames here, he works for nhk, which is the Japan Broadcasting Corporation, and they created the BT 2020 standard. Actually, Masoka led that. And so maybe I can just, yeah, dive right in and give some background on the design of the BT 2020 primaries. And we say primaries because BT 2020 represents red, green and blue chromaticity primaries that are used for RGB displays. He says it here. The system colorimetry for ultra high definition TV. That was their sort of principal goal in creating BT 2020. We already had a standard for HDTV, which is REC 709. Probably many of your audience are familiar with REC 709 HD color. And their goal was to create something new for ultra HDTV that would expand the color in the way that the resolution was being expanded as well. They first presented this work at idw, that's International Display Workshop. It's in Japan, kind of a sister conference to the SID display week back in 2009. Now, one of the goals, and this is one of the kind of interesting points about BT 2020. Many people think that BT 2020 is, quote, unquote, just a container gamut that's designed to contain all of the other color gamuts. Well, that was one of the goals that when they created BT 2020. But they also had some other things in mind. And we'll talk about that as we go through. So you look here at the XY or CIE 1931 chromaticity chart on the right. Your audience is probably pretty familiar with this chart. The kind of horseshoe shaped or guitar pick, depending on your perspective. Shape here represents the range of colors that the human eye can see. And we use these sort of arbitrary X, little X and little Y coordinates to represent chromaticity, which is sort of an abstraction of, you know, hue and saturation. But Importantly, not luminance. And the color gamut or chromaticity gamut of any display is represented by a triangle which contains primaries, a blue point, a green primary and a red primary. And that shows the range of colors the display can reproduce. So we see BT709 here, which is that HDTV spec. We see DCI P3, which is kind of the cinema spec, and our Adobe RGB which is used with photographers and people doing print graphics. It's kind of another popular wide color gamut. One of the goals for Masaoka san was of course to cover those existing standard gamuts. And another objective that he had was to select color primaries on the spectral locus within certain wavelength ranges that would allow them to cover the standard gamuts. Spectral locus. Now we're really getting into some sort of geeky terminology.
- [07:14]
Scott Wilkinson
Super geeky. I dig it. I like it.
- [07:17]
Jeff Urich
So the spectral locus is this line at the outside of the horseshoe shape here. And it represents pure monochromatic wavelengths of light at the edge of the diagram. And let's see. So you can see them labeled here. So you kind of start at 360 down here in the lower left, up through the four hundreds blues into cyan, sort of high four hundreds green. You're sort of in the mid five hundreds. And then you get to red starting at around 600 nanometers. That's nanometers of wavelength for the light. And so he wanted to pick pure colors of light that would allow him to efficiently. He doesn't save that here, but that was part of the objective. Cover these standard gamuts. So green he fixed on 532 nanometers of wavelength. You can see the green primary at the top there. Red he selected at 630nm, way down in the right there. This was interesting to me. I did not know this until the presentation, but this is an international standard and there were some international back and forth here as they centered on what would the peak wavelength be. Japan apparently wanted 635, which is an even deeper red. Korea wanted 625 and they compromised on 630.
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Scott Wilkinson
Why do you suppose it is that the two countries wanted different wavelengths of red?
- [08:48]
Jeff Urich
I don't know. I have to ask him about that. My guess is it has something to do with energy efficiency and brightness. Our eye is not very sensitive to red light. And the longer wavelengths of red light are much less sensitive to the eye. And so it's one of the challenges for wide color gamut displays. The deeper the red you have, the less nits you have. Nits are a measure of the luminance of a display and they're based on the sensitivity of the eye. The eye is most sensitive to 550 nanometer green, roughly. Right. So kind of a yellow green. That's where we're most sensitive to. The further towards blue you go, and the further towards red you go, the less sensitive your eye becomes. So if you pick a very, very deep red primary, you may have the same number of photons coming out of the display, but you will have a lower number of nits. And so manufacturers never want to give up their nits value.
- [09:50]
Scott Wilkinson
They want it to be as bright as possible.
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Jeff Urich
That's right. So same number of photons, 635 to 625. 625 display will look brighter and have a higher number of nits measured. And so that's probably something to do with why they did that. 635, of course, would be wider color gamut also. So there's some trade off there. So that's the red point, 630Nm. And they also selected 467Nm for the blue point. That's a little bit different than some of the other standards, actually. And it hints at another goal they had, which was the reproduction of real object color. So in addition to reproducing these three standard gamuts, 709 P3, and Adobe Masaoka San was very interested in creating a RGB primaries that would be able to reproduce all the object colors that we see in the world around us.
- [10:48]
Scott Wilkinson
A worthy goal, I would say.
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Jeff Urich
Pretty good goal, yes. So then you can see the BT 2020 triangle filled in there with those three primaries. Got it.
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Jeff Urich
This is something we've already talked about. And another thing that he was thinking a lot about is that gamut is not three dimensional. So as I mentioned, he was looking at reproducing all the colors found in the natural world. A good goal and an ambitious one. And fortunately a guy named Pointer went and did this in the 1980s. He actually went and measured the gamut of surface colors and he looked at thousands of objects, I think over 4,000 objects, and measured the the color of those objects. Now, when you say surface colors, you're only talking about objects with light reflecting off of them, not emissive colors. So there are emissive colors in nature, things like, you know, lava that's sort of emitting its own light. But the man made objects too, like fireworks and neon signs and LED lights. Right. Those are excluded from this study. So you're only looking at sort of, you know, light shining off of a paint swatch or a green leaf or something like that.
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Scott Wilkinson
Right, Right.
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Jeff Urich
And he produced this gamut of real object colors. And that's what you see plotted on each of these three CIE charts. So we're looking at on the left BT709, a sort of gray triangle which you can see, does not cover that blob of the real object colors. Nature not following. You know, Precise triangles like 709. Right, right. More organic shape, which you'd expect. DCIP3 here in the middle. Much better job. But there's still. You can see some cyan missing, some purples missing. You can see some things poking through some colors poking through the gray. And we'll talk about what that means in a second. And then BT 2020, almost perfect coverage. You do see a little bit of cyan peeking out the side there. But this gets to one of the limitations of these 2D chromaticity gamut charts. They are only showing hue and saturation. That's what chromaticity is, sort of hue and saturation. But luminance or brightness is a key component of color, and that's not on these charts. That's why we don't call them color gamuts anymore, because they really aren't col. So there's a cool little animation that he has here that flips these on their back and you can see that big Y axis, the big Y representing luminance. And now you can see a much more complex story start to emerge. And you can see the 709 triangle, for example, is missing those cyans on the side. But then it's also missing some other colors because it's not able to capture them inside the volume. So some of these brighter colors are not captured within 709, even though they fall within the bounds of the triangle. So that flat triangle doesn't tell you the whole story. Same with P3. But then BT 2020, and this was his goal, is really mostly encompassed. In fact, 99.9% covers Pointer's gamut.
- [16:12]
Scott Wilkinson
Very good. This is very cool.
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Jeff Urich
Yeah, really cool visualization. And these are a little bit abstract visualizations. And so if I go to the next slide. Okay, let's see. Yeah, it shows that again, these are showing Sealab plots, and these are actually really real color volumes. Using C Lab, they measure hue and saturation using arbitrary units, which are A star and B star. And you can see a star here and B star. And then luminance is measured in L from 0 to 100. 0 is the black, and 100 is the brightest output of the display, typically white. And it's relative. So, you know, a brighter display doesn't make a bigger blob. It's just, you know, pegged to L100. But it's still a very good Way to compare the color capabilities.
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Scott Wilkinson
So these gray shapes are the color volumes of BT709DCIP3 and BT 2020.
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Jeff Urich
That's right, yep. And the dots are the pointer's gamut data set. And so you can see how well they encompass those colors
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Scott Wilkinson
BT 2020 does the best job.
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Jeff Urich
Does the best job. More than 99.9% of 2020 is of Pointer's gamut is covered by BT 2020. And again in addition to the contain containing the other standard gamut. So that's a really great feature. He also points out that ITUR BT2020 is now standardized by the ITU International Telecommunications Union. SMPTE has it and it's been adopted by HDR tv. So here he says the main purpose was to reproduce real world colors. And one of the things that's people say, well, as we've already said, that's a great goal. Everyone can sort of get behind that idea. Why wouldn't you want to give directors and artists the palette of all of colors in the real world to tell stories with and use? Right. It's great. But can today's light sources cover Pointer's gamut and can they cover BT2020s? Big question.
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Scott Wilkinson
You're talking about a display's light source, right?
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Jeff Urich
Exactly. But we'll go through this here. But he's using more of light source than perfectly a display. And I'll explain why here in a second. But he did a whole paper on this to simulate Poynter's gamut coverage and he assumed some typical light sources. I didn't put him up to this. He happened to pick QDs so I'm happy with that. But he wanted to show because one of the things he gets pushed back on a lot is like look, you can only do this with a laser. Lasers emit pure monochromatic light. And so you can, you know, peg lasers at 467, 532 and 630 and you can get there.
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Scott Wilkinson
And quantum dots do not produce monochromatic light.
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Jeff Urich
They have some sort of bell shaped distribution around the peak. And that's the full width half max. That's the FWHM that measures how wide is the sort of width of the peak. Interestingly, he points out, and he's right, red doesn't really matter. You can have a really broad red as long as you have the right wavelength. And you can still get very far out, very close to the spectral locus, very, very saturated red. You don't want to do that because you lose a lot of Energy. So you want to still have a pretty narrow red just to keep your energy efficiency up, up, but you don't need it purely for, in terms of hitting the color point green. He used a 30 nanometer full with half max, which is pretty conservative. Quantum dots today can outperform that. Even OLEDs can outperform that. And he used a blue LED, which is typically used in quantum dot displays. He used 20 nanometers. And even that also is fairly conservative. I'm certain there's blue LEDs that are a bit, bit narrower than that today. And he creates this chart here that shows, you know, he kind of throws out red because it doesn't really matter. Right. And he shows you this kind of heat map that shows you can get to kind of 99.7% coverage of BT 2020 with a 532 at 30 nanometers and a 467 at 20 nanometers. So he wants to show there is a pathway with available technology to recreate full, essentially full BT 2020 coverage today. And he's got a whole paper here that he published about this. So yes, it is possible. I have a little bit of a nit that I would pick here with this, which is. He doesn't. So when you say light sources versus displays, yes, this is true. You could come to nanosys and I will light up a blue LED and put a green QD in front of it and red, you know, at these wavelengths, and you would get this result. But what he's not covering here is the color filter crosstalk issue. So in an LCD display, you have color filters in the LCD panel and those color filters. Have we talked about this last time, these kind of, you know, these, these crosstalk points and the green tends to leak into the blue and that hurts your blue point. And you end up playing this geometry game and you can never kind of get here, even though the backlight might be able to get here. The front of screen is very.
- [22:09]
Scott Wilkinson
Because of the color filter crosstalk.
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Jeff Urich
Exactly. And so it's very, very challenging, I think. You know, we've done this various times using standard, and we talked about this last time as well. There are specialty filters that allow you to get closer to this. But we don't see the brands willing to adopt those. They, they want to run the factories, very high optimization, and they don't want to shut them down and change the filters. So you kind of are stuck with the filters that are kind of being used today. And you can push to 94, 95, maybe 96. Percent within that. So there is room to grow today for an LCD, but you cannot get to 99.7% I would say with an LCD today.
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Scott Wilkinson
Now you would be able to with electroluminescent quantum dots.
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Jeff Urich
Absolutely right. And we actually see with the blue heat shows a 20 nanometer blue. We see blue QDs emitting in that range. And so you could with electroluminescent quantum dot, which is very exciting. QD OLEDS today are at around 91 coverage and they have some headroom to improve there. And we see RGB OLEDs which are typically found in phones, tablets and increasingly in laptops, although we don't see those in TVs today. I think we'll see sort of 95% coverage RGB OLED displays within the next year or two years. So those things are coming. So he's broadly right. Like the technology is there, but just you're not seeing that in the market today. Today we're sort of capped at around 91 or 92% I would say.
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Scott Wilkinson
Okay.
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Jeff Urich
In terms of coverage on area, we're seeing all we talked about this last time, 130%. I mean pick a number. Right. Brands are saying whatever they want to, but coverage you're not seeing really above 92%, I would say. Right. So NHK being a broadcasting company, they
- [24:20]
Scott Wilkinson
are the national broadcasting company in Japan. Right?
- [24:23]
Jeff Urich
Exactly right. So they wanted to demonstrate a whole end to end system capability here. And so they did a demo in 2013 showing real objects. They have stained glass windows here. They have sort of a sports car, some flowers, some butterflies, whole range of different objects. And they used 8K video with a 3 chip, 8K 120 FPS camera. Wow. With 12 bit analog to digital conversion image sensors. And then piped that into a AK120 hertz 12 bit laser projector to reproduce BT 2020. And I think. Yeah, you'll see a video. So they're showing the scene there and then here's the laser projector showing that scene.
- [25:14]
Scott Wilkinson
Let me ask you a question about that.
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Jeff Urich
Yeah.
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Scott Wilkinson
The stained glass windows would seem to me to be emissive. In a sense. Light is coming through them, but it's emitting from that surface. So it's not exactly part of Pointer's gamma. Right.
- [25:32]
Jeff Urich
I. No, I think those would be included because they are effectively absorbing and only passing through the color that you see. So it is essentially a surface color. Yeah. But there's some interesting work around the early history of quantum dots actually where there were sort of these colloidal nanoparticles that were part of the process of making stained glass windows that are almost like quantum dots. And so in the middle Ages, they were sort of almost on the edge of creating quantum. In these quantum dots.
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Scott Wilkinson
Yeah.
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Jeff Urich
Which is kind of a neat thing.
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Scott Wilkinson
That's pretty cool.
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Jeff Urich
Yeah. One of the guys who got a Nobel Prize for quantum dots was actually exploring that area and sort of looking at that and sort of one of the sort of accidental, you know, ways to discover QDs, actually.
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Scott Wilkinson
Yeah, yeah. Okay. So they did this. They did this sort of test with super, super bad camera and a super bad display.
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Jeff Urich
Right. And so they showed that it works and that you could reproduce these colors. So I think what he's interested in showing the world is like, hey, I really do intend this to be a display gamut. That's sort of where they were going. They also had a whole audio component to. They wanted to 8K. They wanted to do BT 2020 color. And I forget the audio spec, but
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Scott Wilkinson
it was something like 22 channels as I recall.
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Jeff Urich
There you go, 22 channels. I mean, they were just really going for kind of what would be the ultimate kind of, you know, experiential capability. So. Right. Really pushing the limit. And. Yeah. Here you have an image of people looking at that demo. Right. And that was 96% of BT 2020, even with a laser projector there. He also references a 2015, 98% BT 2020 laser projector from 20 from 20 laser backlit LCD.
- [27:36]
Scott Wilkinson
Says there.
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Jeff Urich
Right. So even with a laser, LCD still can't really get to 100% because of those color filters.
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Scott Wilkinson
Right.
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Jeff Urich
They're still subject to that. The crosstalk is so broad that lasers can be almost worse because the laser just puts all the light through, through the crosstalk region. It's very challenging.
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Scott Wilkinson
I don't think I've ever heard of a laser backlit LCD tv. This must be like a prototype or an experimental model or something.
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Jeff Urich
Oh, totally. A prototype. I think I remember seeing this at Display Week back in that time frame. But yeah, not something you'll see on a store shelf.
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Scott Wilkinson
Yeah, right.
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Jeff Urich
So he kind of concludes here, but I have a little bit more I can talk about after this as well, but talks about, you know, BT 2020 enabling this wide color gamut. But the true value, he thinks is in supporting reproduction of real world colors. Gamut rings, which you haven't talked about yet. I kind of pulled it out, but I can go into that next. And that's another invention of Mazaoka's to visualize the color capabilities of display with true color, including luminance in a 2D diagram. And he thinks it helps researchers and engineers and creators and consumers understand wide color gamut displays and wishes us toward a more vibrant future for the display industry.
- [29:00]
Scott Wilkinson
Couldn't agree more.
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Jeff Urich
It's all good stuff.
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Scott Wilkinson
He is a very smart guy.
- [29:07]
Jeff Urich
Yes, totally man.
- [29:11]
Scott Wilkinson
Well that's fantastic.
- [29:13]
Jeff Urich
Yeah. So we can pause here or I can talk a little bit about gamut rings too. I have some material on that too if you want to go.
- [29:19]
Scott Wilkinson
Sure. Let's talk a little bit about Gamma Ring.
- [29:22]
Jeff Urich
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Jeff Urich
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Jeff Urich
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- [31:07]
Scott Wilkinson
I will mention that I did cover them on this show in episode 491 almost a year ago now.
- [31:17]
Jeff Urich
Okay, okay.
- [31:18]
Scott Wilkinson
It was after I met Masaokasan at display week in San Jose.
- [31:23]
Jeff Urich
Nice.
- [31:24]
Scott Wilkinson
And. And I think you and he Introduced me to Gamma gamma gamut rings for the first time. And I thought they were so cool.
- [31:33]
Jeff Urich
Yes.
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Scott Wilkinson
That I covered them on my show. But that was a year ago. So let's try to do a quick little recap here, okay?
- [31:40]
Jeff Urich
Yeah, sure. Do a little refresher course. And believe me, I still need a refresher course on gamut rings. It's a little complex topic, but it's a very, very cool idea that he came up with. And so we'll start by showing you the C lab color volume. Again. You can see this kind of 3D hull shape here. And remember that the kind of hue and saturation are represented by a star and B star coordinates which are minus 200 to 200. And then the luminance is represented by L star. And again that's a relative scale from 0 to 100 L star. And I will start the animation here so you can see it spinning around. And one thing that the first thing that he does is he slices up the l range from 0 to 100 into l 10l steps. So starting from the black, which is 0 up to 10l, then 10 to 20, 20 to 30, all the way up to 90 to 100, that's that 90 to 100 slice at the top.
- [32:49]
Scott Wilkinson
So these are slices of the volume.
- [32:52]
Jeff Urich
Slices of the volume, exactly. So kind of, oh, let me see if I can get the thing playing here. And then he stretches those rings, those slices out and plots them down onto a 2D surface. And so you're able to see effectively that whole 3D whole volume in one slice in one two dimensional image. Exactly. So that middle, sort of like think of tree rings, right, represents 0 to 10 L star. The next ring represents 10 to 20 L star, then 20 to 30 all the way out to this outer One here is 90 to 100. So each L star ring is kind of a self contained view of that slice of luminance. Lightness increases from near black on the inner ring. The hue angle is preserved. And this is also very well standardized with SID CIE and the iec. What's really cool and really useful is to use this in making intersections or coverage comparisons among displays. So you can see you have the BT 2020, that's the gray blob on the bottom here. And now we're looking at a display under test dut display that we're measuring. You measure over 600 color points by the way, to measure the gamut rings or the color, color gamut cap of the display to do this. And you can see the gray area that's peeking through is the standard. So this display is falling pretty well short of covering the BT 2020 reference. And then you can see by looking at the ring sort of which part of the luminance areas might be falling less, more, you know, short, or which are covering the standard better.
- [34:56]
Scott Wilkinson
So the green, in this case the green and yellow area and the blue ish area are covering it better.
- [35:05]
Jeff Urich
Right.
- [35:06]
Scott Wilkinson
Than true green and the red area parts of the image.
- [35:11]
Jeff Urich
Exactly. And I. Yeah. Okay. So you can see here a couple of examples. Like on the left, the BT709 gamut compared to BT 2020. And on the right, the DCIP3 gamut compared to BT 2020. And there's a few numbers in the lower left hand corner. The V DUT is the volume and sort of representing the number of distinguishable colors of the display device under test. First is the vref, which is the reference gamut. And then the sort of ratio of the test device to the reference and then. And then the intersection there. So you can see 709 is really basically 45% coverage of BT 2020. P3 is basically 66% coverage of BT 2020. And that's true color, not just chromaticity.
- [36:09]
Scott Wilkinson
Yeah, that's over the entire luminance or brightness range.
- [36:12]
Jeff Urich
Exactly. And this is one of the demonstrations that he did for me early on that I found actually very compelling. So I wanted to walk you through that.
- [36:21]
Scott Wilkinson
Sure.
- [36:22]
Jeff Urich
Really show the advantage of looking at gamut rings. So we have a tale of two real displays here. The colored triangles are the measured displays, and we're showing it against BT 2020, although these are quite obviously much less than full BT 2020 coverage. But you've just kind of squint at these two triangles. Maybe you're scrolling through kind of a couple of TV reviews and you'd go, well, these are pretty similar. Right. I mean, they look very.
- [36:52]
Scott Wilkinson
They look kind of similar to me.
- [36:54]
Jeff Urich
Right. So yeah. Okay. Pretty similar color performance. And I'll pick based on some other factor. Right. Like I'll assume the color is the same, but if you look at the color volume, you can see there's quite a big difference. So again, you've got that big gray hull representing the target gamut, which was BT 2020. And then the colored hull inside represents the color volume of the display under test.
- [37:21]
Scott Wilkinson
Right. But it's capable of doing.
- [37:24]
Jeff Urich
Right. So right away you can actually see a very. These are very big difference. Right. But you know, one of the challenges for this 3D view is to really understand the difference, you have to turn them both around and look at them underneath. Look at them from above. Right. Because it's this 3D hull.
- [37:39]
Scott Wilkinson
Right.
- [37:39]
Jeff Urich
And so that's where Gamut Rings comes in.
- [37:43]
Scott Wilkinson
Look at that, look at that.
- [37:45]
Jeff Urich
Right. So it's a huge difference. So you can see that whole three dimensional hull in one snapshot from all angles. Right. Because it's all flattened out. And you see the one on the left is actually 26% of BT 2020 while the one on the right is 66%. So the one on the right is a basically full P3 display. The one on the left is actually sub 709 in terms of the color capability.
- [38:12]
Scott Wilkinson
So perfect example of why you don't want to trust that 2D CIE chromaticity diagram.
- [38:20]
Jeff Urich
Right. It really can lead you astray. And so you'd be pretty disappointed if you went home with the one on the left and then found out, gee, like the colors don't really look right here. So.
- [38:31]
Scott Wilkinson
Right.
- [38:32]
Jeff Urich
Oh man. Yeah, that's a pretty severe example. And I think this is a. The one on the left would be some kind of white sub pixel architecture. I would say it's probably not a white OLED. White OLEDs do have the white sub pixel. They can kind of peak the white up. But the white OLED TVs we see on the market today are not to this extreme. So this is like maybe a projector for PowerPoints you find in a boardroom where it's really boosting the white to try to get as much luminance. Or There are some LCDs also that use that architecture that are really severe with peaking the white up to. At the expense of color. So this is, this is like a very, very severe example. But yeah, still
- [39:23]
Scott Wilkinson
cool, man.
- [39:24]
Jeff Urich
Yeah. So that I think that's a great example for why this really matters. So it's cool to see a lot of the reviewers are starting to pick this up. We've seen ratings start to use Gamut rings in their reporting.
- [39:37]
Scott Wilkinson
Which is good because by nature a website or a magazine. I'm dating myself here. I used to work a lot on magazines.
- [39:46]
Jeff Urich
Yeah.
- [39:47]
Scott Wilkinson
Are two dimensional, right. You know that you can't rotate a, a volume, a color volume and see what it looks like from all angles. But this Gamut Rings thing lets you. Gives you a really good picture of what's going on in, in the whole 3D space while being still two dimensional.
- [40:07]
Advertisement Voice
Yeah.
- [40:08]
Jeff Urich
And I love this view where you see the intersection of it. You sort of get used to looking at this and it's like, yeah, the more color you see, you sort of know it's covering more of the gamut. Right. There's very visually obvious. The one on the left is really sub, substandard and the one on the right is getting quite close. So. Yeah, good example. And actually that leads to this other idea that he's been pursuing. And this is a little bit outside of your world, I would say, but. But this is something being used by content creators. And so he's now created a scope that you can use when you're color grading your movie, using gamut rings to visualize every pixel in every frame in gamut rings in real time. And colorists really like this because this is like very information rich in one scope. You kind of get a few different scopes because you're getting luminance information, you're getting hue, you're getting saturation information. And you can really be very precise in terms of the changes that you're making.
- [41:14]
Scott Wilkinson
Look at that. Yeah, so this, this what we're seeing here is, is for colorists and content creators, not for consumers. But I always like to show people what the creators are doing because that affects what they see when they bring a TV home and watch some content.
- [41:34]
Jeff Urich
Exactly. So. Exactly. Instead of just the chromaticity scopes you can see, a colorist might look at the chromaticity scope to see, hey, are my colors falling in. In gamut or in the chromaticity? Maybe they're looking at a vector scope. Right. But really you're getting all of that information in one place on the gamut ring scope. So shows a couple examples here. Like a view of DaVinci resolve. Yeah. Even you're getting the histogram almost. So. Yeah. And then you can pair it with sort of out of gamut mapping. So you can see, wow, there's a
- [42:08]
Scott Wilkinson
lot out of BT709 in this picture.
- [42:11]
Jeff Urich
Exactly. So that's, I mean, hey, if you're trying to ship some BT709 content, you certainly want to know, right?
- [42:18]
Scott Wilkinson
Oh, you can't see most of this color.
- [42:21]
Jeff Urich
Right. You better dial back.
- [42:23]
Scott Wilkinson
Right. All right.
- [42:26]
Jeff Urich
Wow. So, yeah.
- [42:28]
Scott Wilkinson
Well, that is super cool. Was there anything else you wanted to mention?
- [42:31]
Jeff Urich
No, I think that's it. Just got another example there and that was it. So I'll stop.
- [42:37]
Scott Wilkinson
Fantastic. Well, wow, what a geeky time we've had here. Thank you so much.
- [42:42]
Jeff Urich
Thanks. Scott.
- [42:44]
Scott Wilkinson
Your representation of Masaoka san is spot on. Really good. I'm sure he'd be very proud.
- [42:50]
Jeff Urich
Out. Thanks. I hope so too.
- [42:55]
Scott Wilkinson
So Good. Well, that's. That's more than enough to. To keep us occupied for a while. And I want to thank you so much for being here. That's Jeff Urich, VP of marketing at Nanisys, who is also a super home theater geek, if you ask me. Thanks so much, Jeff. Really appreciate it.
- [43:16]
Advertisement Voice
It.
- [43:16]
Jeff Urich
Thanks, Scott. Love being here.
- [43:19]
Scott Wilkinson
Well, I'm sure it'll be again. So there you go. Hope you enjoyed that. Now, if you have a question for me, send it on along to HTG TWIT TV and I'll answer as many as I can right here on the show. And if you have a home theater you're proud of, send me some pics. I'd love to see them. And maybe we'll even get you on the show to show it off to the entire audience. Until next time, geek out. You can't reason with the sun. Trust us, we've tried. This summer, it's time to put that angry ball of fire on mute. Columbia's Omnishade technology is engineered to protect you from the sun's harsh rays that can burn and damage your skin. The sun is relentless, but so is our gear. Level up your summer@columbia.com to spend more time outside and less time slathering on aloe lotion. You're welcome, Columbia. Engineered for whatever.