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What is HDR, anyway?

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Re: What is HDR, anyway?

#101

Post by redczar »

puzzlingcaptcha wrote: post #57
lordleft wrote: post #31

Earlier quoted context omitted.

Isn't that the point of the article? That the colloquial meaning of HDR is quite overloaded, and when people complain about HDR, they mean bad tone-mapping? I say this as someone as close to totally ignorant about photography as you can get; I personally thought the article was pretty spectacular.

But it's not the colloquial meaning, HDR is fairly well defined by e.g. ITU-R BT.2100, which addresses colorimetry, luminance and the corresponding transfer functions.

Colloquial meaning and the well defined meaning are two different things in most cases, right?

Re: What is HDR, anyway?

#102

Post by tart-lemonade »

sandofsky wrote: post #21
gyomu wrote: post #5

As a photographer, I get the appeal of (this new incarnation of) HDR content, but the practical reality is that the photos I see posted in my feeds go from making my display looking normal to having photos searing my retinas, while other content that was uniform white a second prior now looks dull gray. It's late night here so I was reading this article in dark mode, at a low display brightness - and when I got to th…

While it isn't touched on in the post, I think the issue with feeds is that platforms like Instagram have no interest in moderating HDR. For context: YouTube automatically edits the volume of videos that have an average loudness beyond a certain threshold. I think the solution for HDR is similar penalization based on log luminance or some other reasonable metric. I don't see this happening on Instagram any time soon,…

> YouTube automatically edits the volume of videos that have an average loudness beyond a certain threshold.

For anyone else who was confused by this, it seems to be a client-side audio compressor feature (not a server-side adjustment) labeled as "Stable Volume". On the web, it's toggleable via the player settings menu.

https://support.google.com/youtube/answer/14106294

I can't find exactly when it appeared but the earliest capture of the help article was from May 2024, so it is a relatively recent feature: https://web.archive.org/web/20240523021242/https://support.g...

I didn't realize this was a thing until just now, but I'm glad they added it because (now that I think about it) it's been awhile since I felt the need to adjust my system volume when a video was too quiet even at 100% player volume. It's a nice little enhancement.

Re: What is HDR, anyway?

#103

Post by agos »

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…

you are right but at least in my experience it's very easy for a modern iPhone to capture a bad HDR photo, usually because there is some small strong highlight (often a form of specular reflection from a metallic object) that causes everything to be HDR while the photo content wouldn't need it

Re: What is HDR, anyway?

#104

Post by altairprime »

mxfh wrote: post #22

Does anyone else find the hubris in the first paragraph writing as off-putting as I do? "we finally explain what HDR actually means" Then spends 2/3rds of the article on a tone mapping expedition, only to not address the elephant in the room, that is the almost complete absence of predictable color management in consumer-grade digital environments. UIs are hardly ever tested in HDR: I don't want my subtitles to burn…

It seems fine to me. Made sense on the first read and matches my experiences with OpenEXR and ProPhoto RGB and pre-Apple monitors.

High dynamic resolution has always been about tone mapping. Post-sRGB color profile support is called “Wide color” these days, has been available for twenty years or more on all DSLR cameras (such as Nikon ProPhoto RGB supported in-camera on my old D70), and has nothing to do with the dynamic range and tone mapping of the photo. It’s convenient that we don’t have to use EXR files anymore, though!

An HDR photo in sRGB will have the same defects beyond peak saturation at any given hue point, as an SDR photo in sRGB would, relative to either in DCI-P3 or ProPhoto. Even a two-bit black-or-white “what’s color? on or off pixels only” HyperCard dithered image file can still be HDR or SDR. In OKLCH, the selected luminosity will also impact the available chroma range; at some point you start spending your new post-sRGB peak chroma on luminosity instead; but the exact characteristic of that tradeoff at any given hue point is defined by the color profile algorithm, not by whether the photo is SDR or HDR, and the highest peak saturation possible for each hue is fixed, whatever luminosity it happens to be at.

Re: What is HDR, anyway?

#105

Post by lloeki »

mikepurvis wrote: post #32
echo_time wrote: post #7

Note for Firefox users - view the page in Chrome to see more of what they are talking about. I was very confused by some of the images, and it was a world of difference when I tried again in Chrome. Things began to make a lot more sense - is there a flag I am missing in Firefox on the Mac?

Can confirm on Windows 11 with HDR enabled on my display— I see the photos in the article correctly on Chrome and they're a grey mess on Firefox.

On macOS even without HDR enabled on my display there's a striking difference due to better tone mapping between Safari and Firefox.

If I enable HDR the Firefox ones become a gray mess vs the lights feeling like actual lights in Safari.

Re: What is HDR, anyway?

#106

Post by scraptor »

tart-lemonade wrote: post #102
sandofsky wrote: post #21

Earlier quoted context omitted.

While it isn't touched on in the post, I think the issue with feeds is that platforms like Instagram have no interest in moderating HDR. For context: YouTube automatically edits the volume of videos that have an average loudness beyond a certain threshold. I think the solution for HDR is similar penalization based on log luminance or some other reasonable metric. I don't see this happening on Instagram any time soon,…

> YouTube automatically edits the volume of videos that have an average loudness beyond a certain threshold. For anyone else who was confused by this, it seems to be a client-side audio compressor feature (not a server-side adjustment) labeled as "Stable Volume". On the web, it's toggleable via the player settings menu. https://support.google.com/youtube/answer/14106294 I can't find exactly when it appeared but the e…

The client side toggle might be new since 2024 but the volume normalisation has been a thing for a long time.

Re: What is HDR, anyway?

#107

Post by lloeki »

NelsonMinar wrote: post #94

Is there a consensus definition of what counts as "HDR" in a display? What is the "standard dynamic range" of a typical TV or computer monitor? Is it roughly the same for devices of the same age? My understanding is most SDR TVs and computer screens have displays about 200-300 nits (aka cd/m²). Is that the correct measure of the range of the display? The brightest white is 300 nits brighter than the darkest black?

Yes, and not just static but dynamic properties: https://displayhdr.org/performance-criteria/

Re: What is HDR, anyway?

#108

Post by babypuncher »

willquack wrote: post #83
mxfh wrote: post #22

Does anyone else find the hubris in the first paragraph writing as off-putting as I do? "we finally explain what HDR actually means" Then spends 2/3rds of the article on a tone mapping expedition, only to not address the elephant in the room, that is the almost complete absence of predictable color management in consumer-grade digital environments. UIs are hardly ever tested in HDR: I don't want my subtitles to burn…

> That brightness abuse by content I predict HDR content on the web will eventually be disabled or mitigated on popular browsers similarly to how auto-playing audio content is no longer allowed [1] Spammers and advertisers haven't caught on yet to how abusively attention grabbing eye-searingly bright HDR content can be, but any day now they will and it'll be everywhere. 1. https://hacks.mozilla.org/2019/02/firefox-66…

This seems like a fairly easy problem to solve from a UX standpoint, even moreso than auto-playing audio/video. Present all pages in SDR by default, let the user click a button on the toolbar or url bar to toggle HDR rendering when HDR content is detected.

Re: What is HDR, anyway?

#109

Post by mullingitover »

klausa wrote: post #81
sandofsky wrote: post #59

Earlier quoted context omitted.

> Does anyone else find the hubris in the first paragraph writing as off-putting as I do? > "we finally explain what HDR actually means" No. Because it's written for the many casual photographers we've spoken with who are confused and asked for an explainer. > Then spends 2/3rds of the article on a tone mapping expedition, only to not address the elephant in the room, that is the almost complete absence of predictabl…

>No. Because it's written for the many casual photographers we've spoken with who are confused and asked for an explainer. To be fair, it would be pretty weird if you found your own post off-putting :P

Me, routinely, reading things I wrote a while ago: what is this dreck

Re: What is HDR, anyway?

#110

Post by simoncion »

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…

For a year or two after it launched, The Division 2 was a really, really good example of HDR done right. The game had (has?) a day/night cycle, and it had a really good control of the brightness throughout the day. More importantly, it made very good use of the wide color gamut available to it.

I stopped playing that game for several years, and when I went back to it, the color and brightness had been wrecked to all hell. I have heard that it's received wisdom that gamers complain that HDR modes are "too dark", so perhaps that's part of why they ruined their game's renderer.

Some games that I think currently have good HDR:

* Lies of P

* Hunt: Showdown 1896

* Monster Hunter: World (if you increase the game's color saturation a bit from its default settings)

Some games that had decent-to-good HDR the last time I played them, a few years ago:

* Battlefield 1

* Battlefield V

* Battlefield 2042 (If you're looking for a fun game, I do NOT recommend this one. Also, the previous two are probably chock-full of cheaters these days.)

I found Helldivers 2's HDR mode to have blacks that were WAY too bright. In SDR mode, nighttime in forest areas was dark. In HDR mode? It was as if you were standing in the middle of a field during a full moon.

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