Refraction through a height field with one index per channel — the split is in the glass, not painted on.

Thin-film colour over a stretched shell grain — the orders slide as the pointer glances across, pearl one way and blush the other.

A film a few wavelengths thick over a slow flowing ground — the interference tint multiplies the palette instead of replacing it, and the cursor thickens the film so colour travels out behind the hand.

Noise combed along a flow field — the walk re-reads its direction at every step, so the strands curve.

Crumpled brass with a warm room on one side and a cold window on the other — facets return whichever they face.

A warm and a cool field dragged sideways until they smear — five taps along an axis that fans across the frame.

A print rather than a ramp: five screens, one flat colour each, and what keeps it from reading as banding is where they stop — not at a level line but wherever a coarse mesh says.

One broad shaft laid across the frame — the distance to an oriented axis through a tight core and a wide spill, with the far end giving out — and the hand turns the axis.