Night Lords Blue vs Phthalo Blue RS

How close are they?

ΔE 13.8, fair: the same colour family, but not a straight swap. Phthalo Blue RS is a little darker, more saturated, warmer than Night Lords Blue.

Can I use Phthalo Blue RS instead of Night Lords Blue?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Phthalo Blue RS is a little darker, more saturated, warmer than Night Lords Blue.

Can I use Night Lords Blue instead of Phthalo Blue RS?

The same difference applies the other way round: Night Lords Blue is a little lighter, more muted, cooler.

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.