The Fang vs Caspian Blue

How close are they?

ΔE 9.6, close: similar, with a visible difference side by side. Caspian Blue is more muted, cooler than The Fang.

Can I use Caspian Blue instead of The Fang?

Usually, if you are not matching paint already on the model. Close match (ΔE 10). Caspian Blue is more muted, cooler than The Fang.

Can I use The Fang instead of Caspian Blue?

The same difference applies the other way round: The Fang is more saturated, 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.