1. A method of operating an optical see-through display device having a see-through display screen and a camera, the method comprising: displaying on the see-through display screen an image of an object; and while displaying the image of the object, displaying an image of a shadow cast by the object onto a real-world background scene by acquiring via the camera an image of the real-world background scene viewable through the see-through display screen, determining a location of the shadow in the image of the real-world background scene, rendering the image of the real-world background scene to form an enhanced image of the real-world background scene by increasing a brightness of the real-world background scene in the enhanced image of the real-world background scene in a region adjacent to the shadow compared to a brightness within the shadow, and displaying via the see-through display screen the enhanced image of the real-world background scene over and aligned with the real-world background scene.