A LADAR system includes a transmitter configured to emit a directed optical signal. The LADAR system includes an optical aperture through which the directed optical signal is emitted. The optical aperture receives a return optical signal that is based on the directed optical signal. The system includes a detector to generate a measurement by comparing an attribute of the return optical signal to a predefined threshold. The measurement is based on an amount of backscatter in the return optical signal. The system includes an obstructive element that is controllable, based on the measurement, to move either into or out of a path of the return optical signal. The obstructive element is configured to block the return optical signal at least partly. The system includes a focal plane located in the path of the return optical signal. The obstructive element is disposed between the optical aperture and the focal plane.