Primary Blue vs Russian AF Blue

How close are they?

ΔE 13.0, fair: the same colour family, but not a straight swap. Russian AF Blue is a little darker, more muted than Primary Blue.

Can I use Russian AF Blue instead of Primary Blue?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Russian AF Blue is a little darker, more muted than Primary Blue.

Can I use Primary Blue instead of Russian AF Blue?

The same difference applies the other way round: Primary Blue is a little lighter, 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.