a) Mean rms intensity contrasts, obtained from MHD images which are artificially degraded with the wavefront errors produced by the main mirror of Sunrise (cf. Fig. 1b) and subsequently PD reconstructed. rms values are normalised to that of the original MHD images. Error bars denote the corresponding standard deviations obtained from applying the procedure to 10 different snapshots. The solid curves were obtained using a masked pupil and the dotted curves stem from using an annular pupil. The contrast of the images corrected only for diffraction at the entrance pupil is given by the leftmost data point (zero fit coefficients). b) Mean contrasts of the difference images (I_MHD − I_PD)/I_MHD. The dash-dotted curves show the normalised contrast of the original MHD image and the contrast after convolution with the PSF of an ideal annular telescope, averaged over the 10 MHD snapshots.