Transparent Red vs Ink Red

How close are they?

ΔE 7.8, close: similar, with a visible difference side by side. Ink Red is more muted than Transparent Red.

Can I use Ink Red instead of Transparent Red?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Ink Red is more muted than Transparent Red.

Can I use Transparent Red instead of Ink Red?

The same difference applies the other way round: Transparent Red 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.