←back to thread

What is HDR, anyway?

(www.lux.camera)
791 points _kush | 2 comments | | HN request time: 0s | source
Show context
gyomu ◴[] No.43984462[source]
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 the HDR photos I had to turn down my display even more to not strain my eyes, then back up again when I scrolled to the text.

For fullscreen content (games, movies) HDR is alright, but for everyday computing it's a pretty jarring experience as a user.

replies(8): >>43984624 #>>43984641 #>>43984694 #>>43984803 #>>43985865 #>>43986070 #>>43993667 #>>43994385 #
beachwood23 ◴[] No.43984624[source]
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 HDR, and it won’t look half as good.

replies(2): >>43984816 #>>43985129 #
kllrnohj ◴[] No.43985129[source]
> 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 bullshit. The only thing HDR actually does is allow for brighter colors vs. SDR. When used selectively this really enhances a scene. But restraint is hard, and most forms of HDR content production are shit. The HDR images that newer iPhones and Pixel phones are capturing are generally quite good because they are actually restrained, but then ironically both of them have horrible HDR video that's just obnoxiously bright.

replies(4): >>43986322 #>>43988054 #>>43988243 #>>43990073 #
1. LinAGKar ◴[] No.43988243[source]
>HDR can exceed that

It's not just the HDR content that gets brighter, but SDR content too. When I test it in Chrome on Android, if an HDR image shows up on screen the phone start overriding the brightness slider completely and making everything brighter, including the phone's system UI.

>The only thing HDR actually does is allow for brighter colors vs. SDR.

Not just brighter, but also darker, so it can preserve detail in dark areas rather than crushing them.

replies(1): >>43988946 #
2. kllrnohj ◴[] No.43988946[source]
> It's not just the HDR content that gets brighter, but SDR content too. When I test it in Chrome on Android, if an HDR image shows up on screen the phone start overriding the brightness slider completely and making everything brighter, including the phone's system UI.

You have an "old" style handling of HDR on Android. Newer/better devices don't do that (specifically those that support https://source.android.com/docs/core/display/mixed-sdr-hdr )

Similarly MacOS/iOS doesn't do that.

> Not just brighter, but also darker, so it can preserve detail in dark areas rather than crushing them.

It does not get darker, and while PQ allocates more bits to the dark region HLG does not. And, more importantly, neither does the actual display panel which are still typically gamma 2.2-2.4 regardless. So PQ's extra precision in the dark areas is ~never utilized other than as tonemapping input, but the resulting output does not have any increased precision in the darks over SDR.

In fact it actually has less precision in the dark areas as the increased display luminance range means the panels native bit depth need to cover more range.