Probe images from experimental measurements showing the intensity distribution in the focal plane for different probe shapes at an added intensity of 36 × 10⁻⁶ in the DH. Top: two of the three sinc probes, as described in Sect. 4.1 and shown in Fig. 7. Bottom: single-actuator probe centered on actuator 297 (left) and a sharp sinc probe (right). The stripes in the bottom right panel originate from the sharp sinc probe itself; it is aliasing that is introduced by undersampling the sinc with respect to the highest Nyquist-sampled spatial frequency on the DM (see Eq. (14)). These very strong probes provide here a S/N of ~480, and would thus allow creating a DH on a fainter target, or with shorter exposure times.