Ogre Brown vs Nuclear Yellow

How close are they?

ΔE 8.2, close: similar, with a visible difference side by side. Nuclear Yellow is a little lighter, more saturated than Ogre Brown.

Can I use Nuclear Yellow instead of Ogre Brown?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Nuclear Yellow is a little lighter, more saturated than Ogre Brown.

Can I use Ogre Brown instead of Nuclear Yellow?

The same difference applies the other way round: Ogre Brown is a little darker, more muted.

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.