how is HDR different than simply adding more bits for finer steps between the same existing colors?

Question

how is HDR different than simply adding more bits for finer steps between the same existing colors?

In: 6

Answer 1

I assume you mean video HDR and not photography HDR via editing.

HDR includes a few things:

**10-Bit color**: Normal (standard) is 8-bit, meaning 2^8 = 256, so red/green/blue each have 256 levels of saturation/brightness, giving you nearly 17M color combos. 10-bit is 2^10 , which allows for over 1B combos. This leads to finer color accuracy.

**Wider Color Gamut**: normal tv is rec.709, whereas HDR is rec.2020 (though most televisions, and many cameras go only up to P3). [Here is the comparison](https://image.benq.com/is/image/benqco/color-gamut-8?$ResponsivePreset$&fmt=png-alpha), biggest difference is in the greens.

**Higher nit count**: nits are a measurements of brightness, like lumens. For normal content the max is 100 nits. For Dolby Vision it is 10,000 (though many televisions/projectors obviously cannot get that bright).