Why does the chromaticity diagram look like that?

(jlongster.com)

276 points samwillis | 2 comments | 26 Jul 24 18:19 UTC | HN request time: 0s | source

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radicality ◴[26 Jul 24 20:45 UTC] No.41082131[source]▶

Kinda related, but does someone maybe have a good set of links to help understand what HDR actually is? Whenever I tried in the past, I always got lost and none of it was intuitive.

There’s so many concepts there like: color spaces, transfer functions, HDR vs Apple’s XDR HDR, HLG vs Dolby Vision, mastering displays, max brightness vs peak brightness, all the different hdr monitor certification levels, 8 bit vs 10bit, “full” vs “video” levels when recording video etc etc.

Example use case - I want to play iPhone-recorded videos using mpv on my MacBook. There’s hundreds of knobs to set, and while I can muck around with them and get it looking close-ish to what playing the file in QuickTime/Finder, I still have no idea what any of these settings are doing.

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1. jasomill ◴[27 Jul 24 10:44 UTC] No.41085674[source]▶

>>41082131 #

A summary, with pictures:

https://cdn.theasc.com/curtis-clark-white-paper-on-hdr-asc.p...

To better understand the "knobs", consider opening up your iPhone videos in DaVinci Resolve[1] and playing around with the scopes and tools in the color panel.

[1] https://www.blackmagicdesign.com/products/davinciresolve/tra...

replies(1): >>41104234 #

2. radicality ◴[29 Jul 24 22:06 UTC] No.41104234[source]▶

>>41085674 (TP) #

Thanks! Gonna read that doc.

This is actually how I ended up in this rabbit hole :) I wanted to learn Resolve to edit iPhone HDR videos, got Davinci, played around, realized apparently iPhone uses Dolby Vision for hdr for which you need to buy Studio, so I bought Studio… My first goal was to import a short video, have it look correct in Davinci, then try to do a ‘no-op’ render and view the before/after videos side-by-side in QuickTime. Whatever I did the render always looked either bit different or completely different. But I’ll try again with all the new stuff just learned about hdr, thanks!

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