Slate Grey vs IDF Isr. Sand Grey (61-73)

How close are they?

ΔE 14.2, fair: the same colour family, but not a straight swap. IDF Isr. Sand Grey (61-73) is noticeably lighter than Slate Grey.

Can I use IDF Isr. Sand Grey (61-73) instead of Slate Grey?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). IDF Isr. Sand Grey (61-73) is noticeably lighter than Slate Grey.

Can I use Slate Grey instead of IDF Isr. Sand Grey (61-73)?

The same difference applies the other way round: Slate Grey is noticeably darker.

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.