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What is HDR, anyway?

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791 points _kush | 2 comments | 14 May 25 12:46 UTC | HN request time: 0.545s | source
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Terr_ ◴[14 May 25 23:21 UTC] No.43990206[source]▶
> 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 along only while our gaze is aimed at the exact spot the software expects. If you glance anywhere else around the scene, you instead percieve an unrealistically wrong coloration or blur that frustratingly persists no matter how much you squint. These problems will remain until gaze-tracking support becomes standard.

So ultimately these features reduce the realism of the experience. They make it less like being there and more like you're watching a second-hand movie recorded on flawed video-cameras. This distinction is even clearer if you consider cases where "film grain" is added.

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brokenmachine ◴[15 May 25 01:29 UTC] No.43990946[source]▶
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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pfranz ◴[15 May 25 01:42 UTC] No.43991035[source]▶
Check out this old post: https://www.realtimerendering.com/blog/thought-for-the-day/

HDR in games would frequently mean clipping highlights and adding bloom. Prior the "HDR" exposure looked rather flat.

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brokenmachine ◴[15 May 25 04:17 UTC] No.43991796[source]▶
OK, so it doesn't mean real HDR but simulated HDR.

Maybe when proper HDR support becomes mainstream in 3D engines, that problem will go away.

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1. orthoxerox ◴[15 May 25 08:27 UTC] No.43992986[source]▶
It's HDR at the world data level, but SDR at the rendering level. It's simulating the way film cannot handle real-life high dynamic range and clips it instead of compressing it like "HDR" in photography.
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2. nomel ◴[15 May 25 20:56 UTC] No.43999261[source]▶
> Instead of compressing it like "HDR" in photography

That's not HDR either, that's tone mapping to SDR. The entire point of HDR is that you don't need to compress it because your display can actually make use of the extra bits of information. Most modern phones take true HDR pictures that look great on an HDR display.