The value structure of Andrea del Castagno is mid-key: quiet, controlled, and cohesive. Yellow, ochre, sienna: warm hues that Andrea del Castagno deploys as the palette's primary energy. Saturation is deliberately withheld - the beauty here lies in the near-monochromatic gradations rather than colour difference. The saturated accent, #CBBCAC, registers at 6.6% - sparse enough to feel like a deliberate surprise. 57 units of value range underpin the palette's structural clarity: the eye always knows where light falls. Andrea del Castagno's palette 1 carries its own internal logic while remaining in conversation with the artist's broader colour intelligence.