Lupercal Green vs Dark Green Kawanishi

How close are they?

ΔE 7.2, close: similar, with a visible difference side by side. Dark Green Kawanishi is more muted, cooler than Lupercal Green.

Can I use Dark Green Kawanishi instead of Lupercal Green?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). Dark Green Kawanishi is more muted, cooler than Lupercal Green.

Can I use Lupercal Green instead of Dark Green Kawanishi?

The same difference applies the other way round: Lupercal Green is 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.