Hue · Value · Chroma. A Muria Lab tool.
Rows = Value (light to dark) · Columns = Chroma (neutral to saturated). Hatched chips fall outside the shown gamut. A white dot means the chroma was reduced to fit.
Pick Hue, Value or Chroma to isolate just that slice. The rest fades to faint ghosts so you keep your bearings, and the view auto-orients.