ΔE 9.2, close: similar, with a visible difference side by side. Shadow Thorn is a little lighter, cooler than Dark Blue.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Shadow Thorn is a little lighter, cooler than Dark Blue.
The same difference applies the other way round: Dark Blue is a little darker, 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.
See Dark Blue on the colour wheel See Shadow Thorn on the colour wheel
All matches: Dark Blue equivalents · Shadow Thorn equivalents