Top panels: Q_ϕ images and S/N maps for observations performed in P98 (leftmost panels, in H-band) and in P97 (rightmost panels, in J-band). Bottom panels: U_ϕ images. North is up, east is left. Images have been convolved with a 2D Gaussian of 2 pixels width, and the color scale is linear (in arbitrary units). Except for the U_ϕ images, the inner 0.35′′ in radius are masked (larger than the size of the coronagraph).