Relation between the strength of the λ5780 DIB and the reddening for the Antennae Galaxy (green circles for the gas extinction), and other galaxies. For the Antennae Galaxy data, a Galactic reddening E(B − V)gal = 0.041 has been subtracted. Regarding the data for other galaxies, we included two sets of observations for Galactic targets (blue triangles; filled: Puspitarini et al. 2013, open: Friedman et al. 2011), several sets of data for galaxies in the Local Group (inverted salmon triangles: Magellanic Clouds, Welty et al. 2006; filled burgundy “x”: M 31, Cordiner et al. 2011, open burgundy “x”: M 33, Cordiner et al. 2008), a set of measurements through dusty starbursts (black diamonds, Heckman & Lehnert 2000), some measurements in the lines of sight of supernovae (filled blue crosses, Phillips et al. 2013), including one in M 82 (coral pink pentagon, Welty et al. 2014) and our previous results for AM 1353-272 B (red circles and blue stars, Monreal-Ibero et al. 2015b).