Fulgrim Pink vs Lustful Purple

How close are they?

ΔE 20.7, loose: different enough that you should pick on purpose. Lustful Purple is a little darker, more muted, cooler than Fulgrim Pink.

Can I use Lustful Purple instead of Fulgrim Pink?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 21). Lustful Purple is a little darker, more muted, cooler than Fulgrim Pink.

Can I use Fulgrim Pink instead of Lustful Purple?

The same difference applies the other way round: Fulgrim Pink is a little lighter, more saturated, warmer.

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.