Dark Blue Tone vs Petroleum Brown Wash

How close are they?

ΔE 37.5, loose: different enough that you should pick on purpose. Petroleum Brown Wash is a little lighter, more muted, warmer than Dark Blue Tone.

Can I use Petroleum Brown Wash instead of Dark Blue Tone?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 38). Petroleum Brown Wash is a little lighter, more muted, warmer than Dark Blue Tone.

Can I use Dark Blue Tone instead of Petroleum Brown Wash?

The same difference applies the other way round: Dark Blue Tone is a little darker, 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.