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mxfhyesterday at 2:00 PM9 repliesview on HN

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 out my eyes in actual HDR display.

It is here, where you, the consumer, are as vulnerable to light in a proper dark environment for movie watching, as when raising the window curtains on a bright summer morning. (That brightness abuse by content is actually discussed here)

Dolby Vision and Apple have the lead here as a closed platforms, on the web it's simply not predictably possible yet.

Best hope is the efforts of the Color on the Web Community Group from my impression.

https://github.com/w3c/ColorWeb-CG


Replies

sandofskyyesterday at 2:57 PM

> 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 predictable color management in consumer-grade digital environments.

That's because this post is about HDR and not color management, which is different topic.

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Ditiyesterday at 2:37 PM

They also make no mention of transfer functions, which is the main mechanism which explains why the images “burn your eyes” – content creators should use HLG (which has relative luminance) and not PQ (which has absolute luminance) when they create HDR content for the web.

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willquackyesterday at 3:43 PM

> 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-to-block-automa...

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altairprimeyesterday at 4:22 PM

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.

klausayesterday at 2:51 PM

It's a blog for a (fancy) iPhone camera app.

Color management and handling HDR in UIs is probably a bit out of scope.

srameshcyesterday at 4:00 PM

I on the other hand never thought or cared about HDR much before but I remember seeing it everywhere. But I feel the article explains well and clearly with examples, for someone like me who isn't much camera literate.

lordleftyesterday at 2:19 PM

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.

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thfuranyesterday at 6:37 PM

It may not be the best explanation, but I think any explanation of HDR beyond a sentence or two of definition that doesn't mention the mess that is tone mapping is entirely remiss.

frollogastonyesterday at 6:46 PM

It's nonsense that an image/video gets to override my screen brightness, end of story. I want that removed, not even a setting, just gone.

The photo capture HDR is good. That's a totally different thing and shouldn't have had its name stolen.