What this can and cannot tell you

The pigment model

Mixing uses Mixbox, which represents a colour as a blend of four internal pigments. Those are not your pigments. Two inks that look identical on screen can mix very differently, which is why calibrating from your own swatches matters more than any amount of solver cleverness.

Stirring versus overprinting

Stirred mixing assumes an opaque, even layer. A thin transparent ink film on paper does not work that way — most of the light passes through it, bounces off the paper and comes back out. That is what Overprint mode models, and it reaches darker, more saturated colours than stirring the same inks ever will.

Photographs are not measurements

Your camera applies a tone curve and a saturation boost before you see a single pixel. Expect roughly ΔE 2–3 from a flat daylight shot with the paper white sampled, and worse handheld under mixed light. A colour-managed flatbed scan is better, and imports through the same button.

ΔE, roughly

• under 1 — you could not tell them apart side by side
• 1–2 — very close; a good result at the press
• 2–3.5 — close; usually fine unless matching a spot colour
• 3.5–5 — visibly off
• over 5 — a different colour; the palette cannot get there

Licence

Mixing is powered by Mixbox © Secret Weapons, used under CC BY-NC 4.0. That makes this tool non-commercial only.