Comparison of wavelength scales between different solar atlases − IAG atlas: this work; Kitt Peak atlas #1: Kurucz et al. (1984); Kitt Peak atlas #2: Wallace et al. (2011); HARPS LFC atlas: Molaro et al. (2013). Each data point shows the offset between two atlases calculated from a cross-correlation in a 2 nm range (see text). Comparisons between the IAG atlas and the two Kitt Peak atlases are shown in the main plot. Comparison between the HARPS atlas on the one hand and the IAG atlas and the Kitt Peak atlas from Kurucz et al. (1984) are shown in the inset. Only regions with little telluric contamination are shown.