Before revision: If the observer has perfect vision, the image of the surface is also formed on the retina, and movement of the head will result in the speckle pattern and the surface moving together so that the speckle pattern remains stationary with respect to the URL
After revision: If the observer has perfect vision, the image of the surface is also formed on the retina, and movement of the head will result in the speckle pattern and the surface moving together so that the speckle pattern remains stationary with respect to the background.