Degree (in %, left panel) and angle (in degrees, right panel) of polarisation as a function of wavelength (in nm) for the three apertures in the central region of NGC 1068. Very centre refers to the very inner 0.2″, off-centre to the region with an offset on the torus extension direction, and central region to the large aperture integrating all the flux. See text of Sect. 3.3 for more details about these apertures.