Radial profiles for EW(λ5780.5) (top) and the extinction (bottom) as derived from Hα/Hβ for the approaching (stars and blue lines) and receding (circles and red lines) sides. The horizontal bars traversing the filled symbols mark the radial extent over which the spectra were co-added. In the upper plot, filled symbols indicate measurements without correction, while open symbols include the maximum correction for the contamination of the stellar feature at λ5782 Å.