Closed-loop results with the iMZ on 1 second of turbulence, for 0.4 arcsecond seeing, with tip-tilt pre-correction. Upper panel: evolution of the residual phase variance (rad²) during 1000 iterations of correction at 1 kHz for different flux conditions (magnitude 5 ≤ m ≤ 14). Lower panel: residual phase variance (rad²) and Strehl ratio (averaged over the last 500 iterations) as a function of the number N of inward pho-tons/pixel/frame. The blue crosses indicates the photon noise limit of the iMZ (1.5/N) according to the theoretical variance in Sect. 3.