Wirebook › Glossary › HDR (high dynamic range)
What is HDR (and why does it sometimes look washed out)?
In one sentence: A way of describing pictures with much brighter highlights, deeper shadows and more colours than ordinary video; the screen then squeezes it into what it can actually show.
A little more
An ordinary (SDR) picture describes brightness on a scale made for screens of decades ago, roughly up to 100 nits. HDR video and games describe light much more like the real world: deep shadows, ordinary white paper, and highlights such as the sun or a lamp many times brighter, plus a wider range of colours. The signal says how bright each part should be, up to a peak of 1,000 nits or more.
Your screen then has to fit that into what it can actually show, which is called tone mapping. A bright TV shows most of it; a dim one has to squash it, and often darkens the whole picture to make room for highlights, which is why HDR can look grey or dull. Consoles and PCs offer an HDR calibration step so games know where your screen's limits are, and the TV must have its HDMI input set to its enhanced mode to receive HDR at all.
See it in action
- BonusWhy does a game judder when it can't keep up?A screen is a flip book with a thumb that turns the page on a steady beat, and the game is an artist drawing the pages.9 min · interactive
- BonusWhy does the TV say "No signal"?Before any picture appears, a console and a TV shake hands: the TV says hello, hands over a menu card of every picture it can show, the console picks the best one on both lists, and for films they swap a secret password.9 min · interactive
Do it for real
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