Joint distributions of parameters obtained from the prayer bead method using the subarray mode observations. The x-axis corresponds to radius ratios for all the panels. The top panel is the fit of the central time, the middle and bottom panel, correspond to the impact parameter and the scale of the system respectively. The diamonds with error bars correspond to the results obtained from the observations of visit 1 (Désert et al. 2009). The dashed red lines correspond to linear fits of the points from visit 3, and reveal the correlations between R_p/R_⋆, b and a/R_⋆.