Instantaneous Strehl ratio and the average dark-hole contrast as a function of time. The setup consists of an AO system, an APP corona-graph, and an imaging camera. The AO operates at 1 kHz and is driven to minimize phase errors. There are no NCPAs in this simulation. The dashed gray lines are purely for comparison, as they correspond to time stamps at which NCPAs are estimated in later simulations. The dashed blue line indicates the average Strehl ratio and the dashed red line indicates the average raw contrast for the case when there are no NCPAs and the AO is driven to flatten the wavefront.