Dry Blood vs Dark Umber

How close are they?

ΔE 17.5, loose: different enough that you should pick on purpose. Dark Umber is a little darker, more muted, warmer than Dry Blood.

Can I use Dark Umber instead of Dry Blood?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Dark Umber is a little darker, more muted, warmer than Dry Blood.

Can I use Dry Blood instead of Dark Umber?

The same difference applies the other way round: Dry Blood 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.