Top panels: HFI fsbeams (full line) for two individual detectors (left, 100-1a; right, 147-7) compared with the corresponding joint best-fit retrieved patterns (dashed line); the left panel is representative of a good fit, and the right one of a poor fit. Bottom panels: difference in power between the above patterns, integrated up to a given radial angle, as a function of that angle; the difference between the measured patterns and the RFFM patterns (initial condition) is also shown (red curves).