Bootstrapping with the help of the GSC. Top: images delivered by the GSC at a time. t = 0 represents the beginning of the servo-loop. The frame rate of the AO loop is still fixed at 2 ms with r0 = 12 cm and r_mod = 3λ/D. Bottom: OG estimate during bootstrapping for the corresponding images on the left. Lower OG corresponds to higher residuals on the pyramid, hence to the first frames of loop closure.