A method for cleaning a region of a pool, the method may include moving a pool cleaning robot along a cleaning path that covers the region while acquiring, at first different points of time and by a sensing unit of the pool cleaning robot, first images of first scenes, at least one first scene at each first point of time; wherein the acquiring of the first images is executed while illuminating the first scenes by the pool cleaning robot; detecting, in at least one first image, illumination reflected or scattered as a result of the illuminating of the first scenes; removing from the at least one first image information about the illumination reflected or scattered; determining, based at least in part of on the first images, first locations of the pool cleaning robot; and wherein the moving is responsive to the first locations of the pool cleaning robot.