Mixing recipe
How to mix neutral grey
Target
#808080
Recipe mixes to #808080
A true mid grey, the one with no cast at all, takes four tubes from a common box: white and Ivory Black for the value, then Burnt Umber to warm the black's blue undertone and a part of Ultramarine to pull it back. The two corrections cancel and leave a grey that matches to within a quarter of a ΔE.
The recipe
Step by step
Build the pile from the biggest, lightest component and work toward the strongest tinter. Check the pile against each swatch before moving on.
- Start with 5 parts Titanium Whitepile #F6F6F4
- Work in 4 parts Ivory Blackpile #94999E
- Work in 2 parts Burnt Umberpile #8D857F
- Work in 1 part Ultramarine Bluepile #808080
A simpler mix
Ivory Black and white at two to one is the plain version. It is darker than the target and leans slightly blue, which is the black's natural undertone. Fine as a quick palette grey; use the four-paint mix when the grey has to sit between warm and cool colors without picking a side.
What goes wrong
The last two steps are small and opposite, and overshooting either tips the grey warm or cool. Add the umber until the blue cast just disappears, then the Ultramarine until the brown cast does. If you lose track, a smear next to a piece of white paper shows the cast more clearly than the pile does. Ivory Black (tinting strength 4, where a cadmium is 1) is the paint to be careful with here: it goes in last, a knife-tip at a time, and a little too much cannot be mixed back out.
Related colors
Results vary with brand, lighting and medium. Acrylic dries a touch darker than it looks wet. Treat this as a mixing aid, not a lab instrument: it tells you which tubes to reach for and roughly in what proportion. Fine-tune the last stretch by eye.