ΔE 9.4, close: similar, with a visible difference side by side. Carbon Black is a little darker, more muted than Midnight Olive.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Carbon Black is a little darker, more muted than Midnight Olive.
The same difference applies the other way round: Midnight Olive is a little lighter, 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 Midnight Olive on the colour wheel See Carbon Black on the colour wheel
All matches: Midnight Olive equivalents · Carbon Black equivalents