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tokens: the impact of model errors on the performance of the PW+EFC correction loop. We consider the same errors as for PW in Sect. 3.3 : influence function size, translation and rotation of the DM. We use the assumptions of Sect. 3.1 except for the amplitude aberrations. Here they are assumed to be at 10% rms error and their PSD distribution is almost flat so that we may approach the testbed environment of the THD2. The two probes for the PW technique are considered to be the bumps of the actuators 466 and 498. We fix the loop gain at g = 0.5. We simulate 578 actuators in the pupil to calculate the matrix G and we select 550 modes after the EFC SVD. As we study the correction of both amplitude and phase aberrations by a single DM, the correction is done within a half DH spreading from 2 λ / D to 13 λ / D on the horizontal axis and −13 λ / D to 13 λ / D on the vertical axis. After the tenth iteration, the contrast level C is computed as the 1 σ azimutal standard deviation of the intensity in the coronagraphic science image divided by the maximum of the non-coronagraphic point spread function (PSF). The results are shown in Fig. 6 . In each plot, the full line is the performance with no model error. Model errors can strongly impact both the WFS (Sect. 3.3 ) and the WFC. In order to reach a 10 −7 contrast level, the size of the influence function has to be known with less than 25% error, the translation of the modeled DM relative to the true one should be less than 0.5 pitch and the orientation of the modeled DM should be better than 1°. Fig. 6. RMS contrast as a function of the angular separation for different cases of model errors when implementing PW+EFC. Model errors simulated are the size of the influence function ( left ), a lateral translation of the DM ( center ), and a rotation of the DM ( right ). 5. Lab performances: wavefront sensing and control on the THD2 bench 5.1. Bench description We compared the two wavefront sensing and control techniques described above on a HCI testbed developed at LESIA (Observatoire de Paris). The optical testbed, called THD2 for trés haute dynamique , is located in an ISO7 pressurized clean room. It is described in detail in Baudoz et al. (2018a) and its layout is shown in Fig. 7 . In this paper, we used the following components: Fig. 7. Layout of the THD2 bench presenting different optical components. – An optical single mode fiber providing a monochromatic light source of wavelength 783.25 nm with a bandwidth less than 2 nm. The focal length of the first off-axis parabola (500 mm) flattens the Gaussian output of the fiber over the pupil diameter. The resulting amplitude aberration allows to reach a contrast level below 10 −7 at 1 λ / D . – An entrance pupil of 8.23 mm diameter. – 32 × 32 Boston-Micromachine (DM3) settled in pupil plane 2. – A FQPM located at the focal plane 3 in Fig. 7 . – A Lyot-stop of 8 mm diameter in the pupil plane 3 (corresponding to a Lyot filtering of 97.2%). In this Lyot plane, a