Hydra Turquoise vs Morning Sky

How close are they?

ΔE 8.7, close: similar, with a visible difference side by side. Morning Sky is more muted than Hydra Turquoise.

Can I use Morning Sky instead of Hydra Turquoise?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Morning Sky is more muted than Hydra Turquoise.

Can I use Hydra Turquoise instead of Morning Sky?

The same difference applies the other way round: Hydra Turquoise is 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.