Contrast iterations on hardware, using EFC to calculate DM commands. The data sets were taken sequentially with single actuators (blue), classic sinc probes (orange), and sharp sinc probes (green), all using three pairs in the PW estimation. The loop was run at a wavelength of λ = 783 nm and with a loop gain of 0.4, and both the mean (full lines) and rms (dotted lines) contrast was measured in a circular DH spanning 3–9 λ/D. All three shapes of probes were applied with a probe amplitude that adds a mean contrast of 10⁻⁶ to the DH in each iteration. The loops were started from the same pre-corrected DM settings each time, at a flux level that would not saturate the focal plane. This slightly limited the achieved contrast later on, but the bench is always limited by diffusion at this level. All three probes reach a DH mean contrast of 3.0 × 10⁻⁸ and a DH rms contrast of 1.7 × 10⁻⁸ after 50 iterations, showing no performance difference at moderate probe amplitudes.