Night Lords Blue vs Ultramar Blue

How close are they?

ΔE 8.4, close: similar, with a visible difference side by side. Ultramar Blue is warmer than Night Lords Blue.

Can I use Ultramar Blue instead of Night Lords Blue?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Ultramar Blue is warmer than Night Lords Blue.

Can I use Night Lords Blue instead of Ultramar Blue?

The same difference applies the other way round: Night Lords Blue is cooler.

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.