ΔE 7.0, close: similar, with a visible difference side by side. Witching Hour Blue is a little lighter than Royal Blue.
✓ Two Thin Coats comparison chart lists these two as equivalents.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Witching Hour Blue is a little lighter than Royal Blue.
The same difference applies the other way round: Royal Blue is a little 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.
See Royal Blue on the colour wheel See Witching Hour Blue on the colour wheel
All matches: Royal Blue equivalents · Witching Hour Blue equivalents