Generator
A chromatic line screen at 1.7 cycles per degree
The upper strip is the pattern as delivered and the lower one is the same pattern after each opponent channel has been low-passed at its own cutoff. Against a flat field of the same mean, the delivered pattern differs by up to ΔE00 14.22 and the filtered one by 13.30 — a ratio of 1.1. Every number quoted elsewhere for a difference of this kind is the first one.
Drawn at its defaults, in the eye as a spatial instrument. It takes no options at all, so every essay calling it gets this exact drawing.
Called by 2 essays
the blast radius of changing it
Difference and uniformity
A difference has no size
A colour difference formula answers a question about two large patches seen side by side. Applied to a pattern, it reports fourteen units where the eye is left with less than one — and the ratio depends on nothing but how finely the difference is spread.
Where the model breaksBanding is not a bit depth
Eight bits bands at thirty times threshold in the shadows and at under three at mid grey, on the same ramp with the same encoding. What decides is where in the tone scale the gradient sits, how sharp each step's edge is, and how far away the reader is — and a bit count contains none of the three.