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What is HDR, anyway?

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Re: What is HDR, anyway?

#251

Post by SchemaLoad »

babypuncher wrote: post #121
aidenn0 wrote: post #62

> A big problem is that it costs the TV, Film, and Photography industries billions of dollars (and a bajillion hours of work) to upgrade their infrastructure. For context, it took well over a decade for HDTV to reach critical mass. This is also true for consumers. I don't own a single 4k or HDR display. I probably won't own an HDR display until my TV dies, and I probably won't own a 4k display until I replace my work…

Pretty much any display you can buy today will be HDR capable, though that doesn't mean much. I think the industry is strangling itself putting "DisplayHDR 400" certification on edgelit/backlit LCD displays. In order for HDR to look "good" you either need high resolution full array local dimming backlighting (which still isn't perfect), or a panel type that doesn't use any kind of backlighting like OLED. Viewing HDR…

HDR marketing on monitors almost seems like a scam. Monitors will claim HDR compatibility when what they actually means is they will take the HDR data stream and display it exactly the same as SDR content because they don't actually have the contrast and brightness ability of a proper HDR monitor.

Re: What is HDR, anyway?

#252

Post by sandofsky »

dahart wrote: post #123

It seems like a mistake to lump HDR capture, HDR formats and HDR display together, these are very different things. The claim that Ansel Adams used HDR is super likely to cause confusion, and isn’t particularly accurate. We’ve had HDR formats and HDR capture and edit workflows since long before HDR displays. The big benefit of HDR capture & formats is that your “negative” doesn’t clip super bright colors and doesn’t…

> It seems like a mistake to lump HDR capture, HDR formats and HDR display together, these are very different things.

These are all related things. When you talk about color, you can be talking about color cameras, color image formats, and color screens, but the concept of color transcends the implementation.

> The claim that Ansel Adams used HDR is super likely to cause confusion, and isn’t particularly accurate.

The post never said Adams used HDR. I very carefully chose the words, "capturing dramatic, high dynamic range scenes."

> Previously when you took a photo, if you over-exposed it or under-exposed it, you were stuck with what you got. Capturing HDR gives the photographer one degree of extra freedom, allowing them to adjust exposure after the fact.

This is just factually wrong. Film negatives have 12-stops of useful dynamic range, while photo paper has 8 stops at best. That gave photographers exposure latitude during the print process.

> Ansel Adams wasn’t using HDR in the same sense we’re talking about, he was just really good at capturing the right exposure for his medium without needing to adjust it later.

There's a photo of Ansel Adams in the article, dodging and burning a print. How would you describe that if not adjusting the exposure?

Re: What is HDR, anyway?

#253

Post by vlmutolo »

Sohcahtoa82 wrote: post #133
nfriedly wrote: post #34

Earlier quoted context omitted.

A lot of monitors that advertise HDR support really shouldn't. Many of them can decode the signal but don't have the hardware to accurately reproduce it, so you just end up with a washed out muddy looking mess where you're better off disabling HDR entirely. As others here have said, OLED monitors are generally excellent at reproducing a HDR signal, especially in a darker space. But they're terrible for productivity w…

I think an OLED is basically an absolute necessity for HDR content. My current monitor is an OLED and HDR in games looks absolutely amazing. My previous was an IPS that supported HDR, but turning it on caused the backlight to crank to the max, destroying black levels and basically defeating the entire purpose of HDR. Local dimming only goes so far.

Modern mini-led monitors are very good. The “local” dimming is so local that there isn’t much light bleed even in the worst-case situations (cursor over black background makes it particularly apparent).

The advantage of LEDs is they’re brighter. For example, compare two modern Asus ProArt displays: their mini-LED (PA32UCXR) at 1600 nits and their OLED (PA32DC) at 300ish nits. The OLED is 20% more expensive. These two monitors have otherwise comparable specs. Brightness matters a lot for HDR because if you’re in a bright room, the monitor’s peak brightness needs to overpower the room.

Plus for color managed work, I think LED monitors are supposed to retain their calibration well. OLEDs have to be frequently recalibrated.

And so-called micro-LEDs are coming soon, which promise to make “local” so small that it’s imperceptible. I think the near-term future of displays is really good LEDs.

Re: What is HDR, anyway?

#254

Post by lotrjohn »

theshackleford wrote: post #231
arghwhat wrote: post #153

Earlier quoted context omitted.

Arguably, even considering HDR a distinct thing is itself weird an inaccurate. All mediums have a range, and they've never all matched. Sometimes we've tried to calibrate things to match, but anyone watching SDR content for the past many years probably didn't do so on a color-calibrated and brightness calibrated screen - that wouldn't allow you to have a brightness slider. HDR on monitors is about communicating conte…

> but your monitor manages 1000-1500 and only in a small window. Owning a display that can do 1300+ nits sustained across a 100% window has been the biggest display upgrade I think I have ever had. It's given me a tolerance for LCD, a technology I've hated since the death of CRTs and turned me away from OLED. There was a time I would have said i'd never own a non OLED display again. But a capable HDR display changed…

Hello fellow CRT owner. What is your use case? Retro video games? PC games? Movies?

Re: What is HDR, anyway?

#256

Post by pornel »

CarVac wrote: post #3

HDR on displays is actually largely uncomfortable for me. They should reserve the brightest HDR whites for things like the sun itself and caustics, not white walls in indoor photos. As for tone mapping, I think the examples they show tend way too much towards flat low-local-contrast for my tastes.

Most "HDR" monitors are junk that can't display HDR. The HDR formats/signals are designed for brightness levels and viewing conditions that nobody uses.

The end result is a complete chaos. Every piece of the pipeline doing something wrong, and then the software tries to compensate for it by emitting doubly wrong data, without even having reliable information about what it needs to compensate for.

https://docs.google.com/document/d/1A__vvTDKXt4qcuCcSN-vLzcQ...

Re: What is HDR, anyway?

#257

Post by pornel »

the__alchemist wrote: post #4

So, HN, are HDR monitors worth it? I remember ~10 years ago delaying my monitor purchase for the HDR one that was right around the corner, but never (in my purchasing scope) became available. Time for another look? The utility of HDR (as described in the article) is without question. It's amazing looking at an outdoors (or indoors with windows) scene with your Mk-1 eyeballs, then taking a photo and looking at it on a…

HDR when it works properly is nice, but nearly all HDR LCD monitors are so bad, they're basically a scam.

The high-end LCD monitors (with full-array local dimming) barely make any difference, while you'll get a lot of downsides from bad HDR software implementations that struggle to get the correct brightness/gamma and saturation.

IMHO HDR is only worth viewing on OLED screens, and requires a dimly lit environment. Otherwise either the hardware is not capable enough, or the content is mastered for wrong brightness levels, and the software trying to fix that makes it look even worse.

Re: What is HDR, anyway?

#258

Post by glenngillen »

Terr_ wrote: post #243

> Our eyes can see both just fine. This gets to a gaming rant of mine: Our natural vision can handle these things because our eyes scan sections of the scene with constant adjustment (light-level, focus) while our brain is compositing it together into what feels like a single moment. However certain effects in games (i.e. "HDR" and Depth of Field) instead reduce the fidelity of the experience. These features limp alo…

I had a similar complaint with the few 3D things I watched when that has been hyped in the past (e.g., when Avatar came out in cinemas, and when 3D home TVs seemed to briefly become a thing 15 years ago). It felt like Hollywood was giving me the freedom to immerse myself, but then simultaneously trying to constrain that freedom and force me to look at specific things in specific ways. I don't know what the specific solution is, but it struck me that we needed to be adopting lessons from live stage productions more than cinema if you really want people to think what they're seeing is real.

Re: What is HDR, anyway?

#259

Post by agrnet »

Terr_ wrote: post #243

> Our eyes can see both just fine. This gets to a gaming rant of mine: Our natural vision can handle these things because our eyes scan sections of the scene with constant adjustment (light-level, focus) while our brain is compositing it together into what feels like a single moment. However certain effects in games (i.e. "HDR" and Depth of Field) instead reduce the fidelity of the experience. These features limp alo…

This is why I always turn off these settings immediately when I turn on any video game for the first time. I could never put my finger on why I didn’t like it, but the camera analogy is perfect

Re: What is HDR, anyway?

#260

Post by brokenmachine »

Terr_ wrote: post #243

> Our eyes can see both just fine. This gets to a gaming rant of mine: Our natural vision can handle these things because our eyes scan sections of the scene with constant adjustment (light-level, focus) while our brain is compositing it together into what feels like a single moment. However certain effects in games (i.e. "HDR" and Depth of Field) instead reduce the fidelity of the experience. These features limp alo…

I'm with you on depth of field, but I don't understand why you think HDR reduces the fidelity of a game.

If you have a good display (eg an OLED) then the brights are brighter and simultaneously there is more detail in the blacks. Why do you think that is worse than SDR?

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