Francis Gruber keeps values measured and balanced, a hallmark of tonal restraint. Francis Gruber tilts toward cool - blues and silver-greys carry the structural weight. Chroma is kept low across all colours, producing the soft, enveloping quality that characterises tonal painting. Only 6.3% is devoted to #5B6214, yet that small allocation delivers the palette's entire chromatic tension. At 62 units of value range, the palette has the tonal breadth to sustain complex spatial readings. The mid-to-high key, cool bias, and moderate chroma point to outdoor observation - sky and diffused daylight as the dominant light source. In the context of Francis Gruber's full range of palettes, group 4 represents one movement in an ongoing chromatic dialogue.