Field Grey Base #2 (Grey Uniform) vs Eshin Grey

How close are they?

ΔE 9.6, close: similar, with a visible difference side by side. Eshin Grey is a little lighter, more muted than Field Grey Base #2 (Grey Uniform).

Can I use Eshin Grey instead of Field Grey Base #2 (Grey Uniform)?

Usually, if you are not matching paint already on the model. Close match (ΔE 10). Eshin Grey is a little lighter, more muted than Field Grey Base #2 (Grey Uniform).

Can I use Field Grey Base #2 (Grey Uniform) instead of Eshin Grey?

The same difference applies the other way round: Field Grey Base #2 (Grey Uniform) is a little darker, more saturated.

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.