Daytime optical observations, including solar telescope and free-space optical communication, experience strong turbulence and scintillation. These conditions cause control problems in Multi-Conjugate Adaptive Optics (MCAO). Considering an MCAO setup with two deformable mirrors (DMs) and wavefront sensors (WFSs), when the system is active, downstream DM distorts image and control of upstream DM at WFSs. Scintillation and shift in position of upstream DM’s actuator at the WFSs induced by active downstream DM are major error sources. Distorted control of upstream DM was simulated including propagation effect with downstream DM correcting a turbulence layer. With flattened downstream DM, upstream DM with distorted control was used to correct a static turbulence. Regions with log-amplitude variance between 0.1 and 0.3 and actuator statistical shift between 10% and 50% WFS subaperture may have partial correction. Regions with extremely low and high distortion have no impact in performance and no AO correction, respectively.
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