ΔE 8.0, close: similar, with a visible difference side by side. Dark Seagray BS381C/638 is more muted than Nocturne Green.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). Dark Seagray BS381C/638 is more muted than Nocturne Green.
The same difference applies the other way round: Nocturne Green is more saturated.
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 Nocturne Green on the colour wheel See Dark Seagray BS381C/638 on the colour wheel
All matches: Nocturne Green equivalents · Dark Seagray BS381C/638 equivalents