Pieter Casteels II distributes its values across the middle register, creating harmony without high contrast. Pieter Casteels II tilts toward cool - blues and silver-greys carry the structural weight. Saturation is deliberately withheld - the beauty here lies in the near-monochromatic gradations rather than colour difference. #5F5139 functions as the palette's exclamation mark: highest chroma, lowest percentage (11.2%). Value range is moderate at 37 units - enough contrast for legibility, not so much as to fragment the tonal unity. High luminosity and cool temperature suggest the plein-air condition: unfiltered daylight and open sky. Pieter Casteels II's palette 5 carries its own internal logic while remaining in conversation with the artist's broader colour intelligence.