Dark Wood vs Transparent Brown

How close are they?

ΔE 7.5, close: similar, with a visible difference side by side. Transparent Brown is more saturated, cooler than Dark Wood. They are different kinds of paint: Army Painter Dark Wood is a one-coat contrast-style paint and Green Stuff World Transparent Brown is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.

Can I use Transparent Brown instead of Dark Wood?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Transparent Brown is more saturated, cooler than Dark Wood. They are different kinds of paint.

Can I use Dark Wood instead of Transparent Brown?

The same difference applies the other way round: Dark Wood is more muted, warmer.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.