Wavefronts from the testing on 3/21/08 using the rotating atmospheric turbulence simulator plate. On the left is the residual wavefront, as measured by the closed-loop wavefront sensor during closed loop operation. In the middle is the reconstructed wavefront using data from the open-loop wavefront sensor. On the right is the DM shape (actually, the voltages being sent to the DM) with the system operating in closed loop, i.e. controlled using the closed-loop wavefront sensor. The data are all simultaneous. Notice that when the turbulence simulator motor sticks, the residual gets low, and more "white noise" (spatially decorrelated) in appearance as expected. But when the motor jerks loose and the "wind" is blowing by fast, the wavefront pattern is imprinted on the residuals i.e. demonstrates a control bandwidth lag error.