Values in John Duncan rest in the mid-range - neither dramatically lit nor steeped in shadow. Blues and teal-greys govern the palette, lending it an aquatic or atmospheric quality. Chroma hovers near zero; colour declares itself through subtle shifts in hue rather than outright saturation. The highest-chroma note - #6D4734 - appears at just 8.1%, deployed as a precision accent against the quieter ground. The value range of 49 units sits in the comfortable middle: enough depth, enough light, neither extreme. The palette has the character of outdoor light: cool, mid-bright, with colour rendered faithfully rather than expressively. Taken together, these qualities constitute John Duncan's chromatic voice - distinctive enough to be read across an entire body of work.