Mid-key values give Henry Ossawa Tanner its characteristic quietness - nothing blazes, nothing disappears. Cool tones set the register here - the blues and greens easily outweigh any warm accents. Muted throughout, the palette achieves its effects through value and temperature rather than chromatic force. At 26.5%, #221E1E functions less as a colour accent and more as a complete atmospheric environment. #181E34 delivers the chromatic peak at only 6.6% - a small shot of colour with outsized visual impact. At 65 units of value range, the palette has the tonal breadth to sustain complex spatial readings. High luminosity and cool temperature suggest the plein-air condition: unfiltered daylight and open sky. This is the light Henry Ossawa Tanner preferred, made measurable.