Sidney Richard Percy distributes its values across the middle register, creating harmony without high contrast. A distinctly cool atmosphere runs through this palette: sky, water, and mist given colour form. Muted throughout, the palette achieves its effects through value and temperature rather than chromatic force. The highest-chroma note - #6E541D - appears at just 4.0%, deployed as a precision accent against the quieter ground. A value spread of 64 units gives the palette both depth and air - shadows are genuinely dark, lights genuinely light. High luminosity and cool temperature suggest the plein-air condition: unfiltered daylight and open sky. This is the light Sidney Richard Percy preferred, made measurable.