Boris Kustodiev is low-key throughout, a quality associated with Nocturnal Sienna - deep shadows dominate the composition. Boris Kustodiev orchestrates warmth above all else - reds, ambers, and siennas take the lead. The absence of saturated colour is itself an expressive choice: this is a palette of restraint and atmosphere. At 39.5%, #1A1819 functions less as a colour accent and more as a complete atmospheric environment. The highest-chroma note - #B57B4D - appears at just 3.0%, deployed as a precision accent against the quieter ground. The full value range is 62 units: broad enough to build convincing three-dimensional form. This tonal restraint is characteristic of the Boris Kustodiev approach: colour serves light, not the reverse. This is palette 21 of Boris Kustodiev's sequence - a single chapter in a chromatic story told across many works.