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What is HDR, anyway?

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Re: What is HDR, anyway?

#231

Post by theshackleford »

arghwhat wrote: post #153
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…

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 that logic in a big way.

Too bad the motion resolution on it, especially compared to OLED is meh. Again, at one point, motion was the most important aspect to me (its why I still own CRTs) but this level of HDR...transformative for lack of a better word.

Re: What is HDR, anyway?

#232

Post by BlueTemplar »

kllrnohj wrote: post #50
beachwood23 wrote: post #18

Earlier quoted context omitted.

Completely agree. To me, HDR feels like the system is ignoring my screen brightness settings. I set my screen brightness to a certain level for a reason . Please don’t just arbitrarily turn up the brightness! There is no good way to disable HDR on photos for iPhone, either. Sure, you can turn off the HDR on photos on your iphone. But then, when you cast to a different display, the TV tries to display the photos in HD…

> To me, HDR feels like the system is ignoring my screen brightness settings. On both Android & iOS/MacOS it's not that HDR is ignoring your screen brightness, but rather the brightness slider is controlling the SDR range and then yes HDR can exceed that, that's the singular purpose of HDR to be honest. All the other purported benefits of HDR are at best just about HDR video profiles and at worst just nonsense bullsh…

It isn't just about the brightness (range).

In practice the 'HDR' standards are also about wider color gamuts (than sRGB), and (as mentioned in parallel) packed into more bits, in a different way, so as to minimise banding while keeping file sizes in check.

Re: What is HDR, anyway?

#233

Post by CharlesW »

sergioisidoro wrote: post #26

Just one other thing. In Analog you also have compensating developers, which will exhaust faster in darker areas (or lighter if you think in negative), and allow for lighter areas more time to develop and show, and hence some more control of the range. Same but to less degree with stand development which uses very low dilutions of the developer, and no agitation. So dodging and burning is not the only way to achieve…

> About HDR on phones, I think they are the blight of photography. No more shadows and highlights.

HDR is what enables you to capture both the darkest shadow detail and the brightest highlight detail.

With SDR, one or both are often simply just lost. It might come down to preference — if you're an "auto" shooter and like the effect of the visual information at the edges of the available dynamic range being truncated, SDR is for you.

Some people prefer to capture that detail and have the ability to decide whether and how to diminish or remove it, with commensurately more control over the artistic impact. For those folks, HDR is highly desirable.

Re: What is HDR, anyway?

#234

Post by dawidpotocki »

brcmthrowaway wrote: post #221
asafira wrote: post #72

I did my PhD in Atomic, Molecular, and Optical (AMO) physics, and despite "optical" being part of that I realized midway that I didn't know enough about how regular cameras worked! It didn't take very long to learn, and it turned out to be extremely important in the work I did during the early days at Waymo and later at Motional. I wanted to pass along this fun video from several years ago that discusses HDR: https:/…

Pixel camera hardware or software? Isnt there only one vendor for sensors - Sony?

Samsung also makes sensors for phones. IIRC some Pixels use their sensors.

Re: What is HDR, anyway?

#235

Post by munificent »

dahart wrote: post #223
munificent wrote: post #213

Earlier quoted context omitted.

"High dynamic range" is a phrase that is much older than tone mapping. I see uses of "dynamic range" going back to the 1920s and "high dynamic range" to the 1940s: https://books.google.com/ngrams/graph?content=dynamic+range%... You might argue that "HDR" the abbreviation refers to using tone mapping to approximate rendering high dynamic range imagery on lower dynamic range displays. But even then, the sentence in que…

> But even then, the sentence in question doesn’t use the abbreviation Yes it does. Why are you still looking at a different sentence than the one I quoted?? HDR in this context isn’t referring to just any dynamic range. If it was, then it would be so vague as to be meaningless. Tone mapping is closely related to HDR and very often used, but is not necessary and does not define HDR. To me it seems like your argument…

Oh, sorry, you're right. Mentioning the abbreviation is a red herring. The full quote is:

"But what if we don't need that tradeoff? What if I told you that analog photographers captured HDR as far back as 1857? Ansel Adams, one of the most revered photographers of the 20th century, was a master at capturing dramatic, high dynamic range scenes. It's even more incredible that this was done on paper, which has even less dynamic range than computer screens!"

It seems pretty clear to me that in this context the author is referring to the high dynamic range of the scenes that Adams pointed his camera at. That's why he says "captured HDR" and "high dynamic range scenes".

Re: What is HDR, anyway?

#236

Post by XorNot »

jiggawatts wrote: post #227
the_af wrote: post #71

Earlier quoted context omitted.

There's a pretty good video on YouTube (more than one, actually) that explains how careless use of HDR in modern cinema is destroying the look and feel of cinema we used to like. Everything is flattened, contrast is eliminated, lights that should be "burned white" for a cinematic feel are brought back to "reasonable" brightness with HDR, really deep blacks are turned into flat greys, etc. The end result is the flat a…

The washed out grey thing was an error that became a style! Because HDR wasn’t natively supported on most displays and software, for a long time it was just “hacked in there” by squashing the larger dynamic range into a smaller one using a mathematical transform, usually a log function. When viewed without the inverse transform this looks horribly grey and unsaturated. Directors and editors would see this aesthetic d…

The transition from Avengers to the later movies is very noticeable, and one of the worst offenders since source material really speaks against the choice.

Re: What is HDR, anyway?

#237

Post by wirybeige »

hbn wrote: post #212
wirybeige wrote: post #86

Earlier quoted context omitted.

I use HDR for general usage, Windows ruins non-HDR content when HDR is enabled due to their choice of sRGB tf. Luckily every Linux DE has chosen to use the gamma 2.2 tf, and looks fine for general usage. I use a mini-led monitor, and its quite decent, except for starfields, & makes it very usable even in bright conditions, and HDR video still is better in bright conditions than the equivalent SDR video. https://githu…

Windows HDR implementation is janky as hell. For months after I got my monitor I couldn't take screenshots because they'd all appear completely blown out, like you cranked the brightness to 300%. Eventually I did some digging and found there's a setting in Snipping Tool that just... makes screenshots work on HDR displays. It also seems to add another layer of Your Desktop Trying To Sort Its Shit Out when launching a…

I always thought the "Your Desktop Trying To Sort Its Shit Out" part was a necessary evil, but other platforms don't suffer from this (at least from what I can tell); the state of HDR on Windows is very disappointing, even just adjusting the TF to gamma 2.2 would make it substantially better. Watching all your non hdr content's blacks become gray is terrible. I assume the washed out appearance comes from it giving up on doing SDR->HDR for the desktop.

My brother got an OLED monitor & was telling me how bad his experience was on Windows, & he recently switched to Linux & does not have the issues he was complaining about before. Ofc, downsides to hdr on Linux (no hdr on chromium, hdr on Firefox is unfinished) atm, but the foundation seems better set for it.

Re: What is HDR, anyway?

#238

Post by qingcharles »

NBJack wrote: post #36
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.

HDR is really hard to get right apparently. It seems to get worse in video games too. I'm a huge fan of Helldivers 2, but playing the game in HDR gives me a headache: the muzzle flash of weapons at high RPMs on a screen that goes to 240hz is basically a continuous flashbang for my eyes. For a while, No Mans' Sky in HDR mode was basically the color saturation of every planet dialed up to 11. The only game I've enjoyed…

A lot of this is poor QA. When you start to do clever things like HDR you have to test on a bunch of properly calibrated devices of different vendors etc. And if you're targeting Windows you have to accept that HDR is a mess for consumers and even if their display supports, their GPU supports it, they might still have the drivers and color profiles misconfigured. (and many apps are doing it wrong or weird, even when they say they support it)

Also (mostly) on Windows, or on videos for your TV: a lot of cheap displays that say they are HDR are a range of hot garbage.

Re: What is HDR, anyway?

#239

Post by qingcharles »

jiggawatts wrote: post #227
the_af wrote: post #71

Earlier quoted context omitted.

There's a pretty good video on YouTube (more than one, actually) that explains how careless use of HDR in modern cinema is destroying the look and feel of cinema we used to like. Everything is flattened, contrast is eliminated, lights that should be "burned white" for a cinematic feel are brought back to "reasonable" brightness with HDR, really deep blacks are turned into flat greys, etc. The end result is the flat a…

The washed out grey thing was an error that became a style! Because HDR wasn’t natively supported on most displays and software, for a long time it was just “hacked in there” by squashing the larger dynamic range into a smaller one using a mathematical transform, usually a log function. When viewed without the inverse transform this looks horribly grey and unsaturated. Directors and editors would see this aesthetic d…

What you said, it's definitely become a style. But, also, a lot of these movies that look like ass on Joe Public's OOGLAMG $130 85" Black Friday TV in his brightly-lit living room actually look awesome if your entire setup is proper, real HDR devices and software, your screen has proper OLED or local dimming, is calibrated to within an inch of its life etc, and you view them in a dark home theater.

Re: What is HDR, anyway?

#240

Post by BlueTemplar »

colechristensen wrote: post #76
reaperducer wrote: post #70

Earlier quoted context omitted.

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 screen, at which point I'll also replace one of my home screens so I can remote into it without scaling. People in the HN echo chamber over-estimate hardware adoption rates. For example, there are millions of people who went straig…

>there are millions of people who went straight from CDs to streaming, without hitting the iPod era Who? There was about a decade there where everyone who had the slightest interest in music had an mp3 player of some kind, at least in the 15-30 age bracket.

I skipped 2 generations for portable music : went straight from cassette to smartphone with MP3 (and radio).
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