Tombstone Yellow vs Krieg Khaki

How close are they?

ΔE 6.1, close: similar, with a visible difference side by side. Krieg Khaki is a little lighter, cooler than Tombstone Yellow.

Can I use Krieg Khaki instead of Tombstone Yellow?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Krieg Khaki is a little lighter, cooler than Tombstone Yellow.

Can I use Tombstone Yellow instead of Krieg Khaki?

The same difference applies the other way round: Tombstone Yellow is a little darker, 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.