Deep Ocean Blue vs Steely Blue

How close are they?

ΔE 7.1, close: similar, with a visible difference side by side. Steely Blue is a little darker than Deep Ocean Blue.

Can I use Steely Blue instead of Deep Ocean Blue?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). Steely Blue is a little darker than Deep Ocean Blue.

Can I use Deep Ocean Blue instead of Steely Blue?

The same difference applies the other way round: Deep Ocean Blue is a little lighter.

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.