Sorting in the LCH Color Space: Jan 2025

C. Kennedy -

See other posts here: Sorting by Color in the LCH Color Space

Two-Stage Rounding Hue and Luminance
Prior state
Hue values rounded up to increments of 20: CEILING.MATH(K2,20)

The problem
Hue values that were very close got pushed far away.

  • 19.9 would round up to 20;
  • 20.1 would round up to 40.

Ideally, 19.9 & 20.1 would end up closer to each other.

Updated State
Hue values round down a small amount and then round up: CEILING.MATH(FLOOR.MATH(K2,5),20)

  • 19.9...
    • Rounds down to 15
    • 15 rounds up to 20
  • 20.1...
    • Rounds down to 20
    • 20 rounds up to 20

Luminance is similar: CEILING.MATH(FLOOR.MATH(I2,3),10)

I think I like the look of it better; I definitely like the math of it better.

Simplifying the Grey Sort
Prior state
Shades of grey, identified as colors with a Chroma value < 4.1, were pushed to the start (lighter greys) and end (darker greys) of the color sort. Otherwise, they sorted the same as non-greys.

The problem
Sorting the greys primarily by Hue looks weird; the low Chroma values make Hue less visually relevant for grey.

Updated

  • I expanded the grey range from 4.1 to 4.9. I may push the range to 5.0 or a little beyond, once I resample some of my colors on the 4.9 border.
  • All greys now have a static value of 360.
  • Instead of rounding Luminance for the greys, I'm using the full value for Luminance.

The net effect of those last two bullet points: I'm ignoring Hue, sorting by non-rounded Luminance, and ignoring Chroma.


Previous sort and current sort

I like the idea of knowing which greys are warmer and which are cooler; in the future, I'll probably look at splitting the greys into a Warm vs. Cool binary.