Different E(B − V) values plotted against each other. Outliers are marked and plotted with error bars. Top panel: some of the stars are connected by a blue line. The left point indicates the reddening at the maximum distance available in the STLISM grid in that particular direction. The right point indicates the reddening estimated at the distance of the Cepheid by a linear extrapolation (see Sect. 4.7 for details). The solid lines indicate the least-squares fir from Table A.2.