Map of differences of z coordinates in R_⊙ for the two clouds of points, overplotted on a map of Log₁₀ of column density as in Fig. 9a. Red regions correspond to where the distance from the plane of sky computed from the polarization ratio technique is overestimated and blue regions correspond to where it is underestimated. The magenta contour roughly identifies the flux rope position where the ratio between the y component of the magnetic field integrated along the LOS divided by the magnetic field intensity is above the arbitrary positive threshold of 0.4.