Night Lords Blue vs Phthalo Blue (Red Shade)

How close are they?

ΔE 17.4, loose: different enough that you should pick on purpose. Phthalo Blue (Red Shade) is noticeably darker, more muted, warmer than Night Lords Blue. They are different kinds of paint: Citadel Night Lords Blue is an opaque base/layer paint and Golden Phthalo Blue (Red Shade) is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.

Can I use Phthalo Blue (Red Shade) instead of Night Lords Blue?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Phthalo Blue (Red Shade) is noticeably darker, more muted, warmer than Night Lords Blue. They are different kinds of paint.

Can I use Night Lords Blue instead of Phthalo Blue (Red Shade)?

The same difference applies the other way round: Night Lords Blue is noticeably lighter, more saturated, 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.