## 3.23 Perception/decoding: Color models HCL (2)

• “we can use RGB to describe colors to the computer but we don’t have to use it as the space where we construct color systems” (Bryan 2020)
• “closer a color model’s dimensions correspond to distinct qualities people can perceive, the more useful it is” (Bryan 2020)
• Hue-Chroma-Luminance (HCL) better reflects how we perceive colors: differentiating between luminance, hue and chroma
• Luminance (Relativity of luminance perception): Perception of how bright something looks
• Hue: What we mean when we use the word “color”: red, blue, green, purple, and so on15
• Chrominance (or chroma): Perception of how intense or vivid the color looks
• Q: Which of the scales illustrates the idea of luminance, chroma and hue? Is there some overlap?

• HCL model realized in the colorspace or Rcolorbrewer packages

### References

Bryan, Jenny. 2020. “STAT 545 Data Wrangling, Exploration, and Analysis with R: Using Colors in R.” https://www.stat.ubc.ca/~jenny/STAT545A/block14_colors.html.

1. Physical terms = dominant wavelength of the light reflected from the object’s surface.