WWI French Green 1 vs Lupercal Green

How close are they?

ΔE 12.6, fair: the same colour family, but not a straight swap. Lupercal Green is a little lighter, more saturated, cooler than WWI French Green 1.

Can I use Lupercal Green instead of WWI French Green 1?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Lupercal Green is a little lighter, more saturated, cooler than WWI French Green 1.

Can I use WWI French Green 1 instead of Lupercal Green?

The same difference applies the other way round: WWI French Green 1 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.