Ritterlich Blue vs Steel Blue

How close are they?

ΔE 7.0, close: similar, with a visible difference side by side. Steel Blue is a little lighter, more muted than Ritterlich Blue.

Can I use Steel Blue instead of Ritterlich Blue?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). Steel Blue is a little lighter, more muted than Ritterlich Blue.

Can I use Ritterlich Blue instead of Steel Blue?

The same difference applies the other way round: Ritterlich Blue is a little darker, 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.