Desert Skin vs Blood Tracker Brown

How close are they?

ΔE 15.5, loose: different enough that you should pick on purpose. Blood Tracker Brown is a little darker, much more saturated than Desert Skin.

Can I use Blood Tracker Brown instead of Desert Skin?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Blood Tracker Brown is a little darker, much more saturated than Desert Skin.

Can I use Desert Skin instead of Blood Tracker Brown?

The same difference applies the other way round: Desert Skin is a little lighter, much 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.