Medieval Forest vs Light Turquois (Phthalo)

How close are they?

ΔE 13.3, fair: the same colour family, but not a straight swap. Light Turquois (Phthalo) is a little lighter, more saturated, cooler than Medieval Forest.

Can I use Light Turquois (Phthalo) instead of Medieval Forest?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Light Turquois (Phthalo) is a little lighter, more saturated, cooler than Medieval Forest.

Can I use Medieval Forest instead of Light Turquois (Phthalo)?

The same difference applies the other way round: Medieval Forest is a little darker, more muted, 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.