ΔE 8.9, close: similar, with a visible difference side by side. Calgar Blue is a little lighter, more saturated, warmer than Power Blue.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Calgar Blue is a little lighter, more saturated, warmer than Power Blue.
The same difference applies the other way round: Power Blue is a little darker, more muted, 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.
See Power Blue on the colour wheel See Calgar Blue on the colour wheel
All matches: Power Blue equivalents · Calgar Blue equivalents