Color representations: A deeper dive into how to represent colors in data visualization
Channel: Lars Juhl Jensen
Date: 2021-08-09

An introduction to complex world of color representation, commonly used representations, their strengths, and their weaknesses. You may want to watch my short introduction to the core concepts of data visualization first:
https://youtu.be/eqmgvf4ChRQ

0:00 Introduction: colors are intuitive but representing them is hard
0:18 RGB: the standard representation of color but terrible for data visualization
0:48 HSV: much better than RGB, but both value and saturation are counter-intuitive
2:12 HSL: lightness works better than value, but saturation becomes even more confusing
3:11 HCL: chroma works much better than saturation, but lightness is still not without issues
4:29 CIELAB: human perception, RGB gets a strange shape, L* matches perceptual lightness, CIELAB is perceptually uniform, and a polar coordinate version exists
6:28 Summary: avoid RGB, use HSV/HSL/HCL for selecting color, and use CIELAB for quantitative data

To work with data visualization in CIELAB, have a look at the U-CIE tool at https://u-cie.jensenlab.org/

Big thanks to Wikimedia Commons user Datumizer, who created all the figures used in this presentation. You can find the originals at https://commons.wikimedia.org/wiki/User:Datumizer