Thunderous Blue vs Payne's Gray

How close are they?

ΔE 9.4, close: similar, with a visible difference side by side. Payne's Gray is a little darker, more muted, warmer than Thunderous Blue. They are different kinds of paint: Army Painter Thunderous Blue is an opaque base/layer paint and Golden Payne's Gray is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.

Can I use Payne's Gray instead of Thunderous Blue?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Payne's Gray is a little darker, more muted, warmer than Thunderous Blue. They are different kinds of paint.

Can I use Thunderous Blue instead of Payne's Gray?

The same difference applies the other way round: Thunderous Blue is a little lighter, more saturated, cooler.

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.