In the first portion of the page, an image shows a man throwing light on a painting with the following text written beside the image: Art forgery detection A technician operates an infrared scanner. He is examining a copy of a painting by the German painter Lucas Cranach the Elder (1472-1553). Second portion of the page shows two images of ultraviolet rays graph and a bluish painting up and below, and between these images, the following text is written: Interpreting ultraviolet radiation Although transparent to visible light, the varnish layer on the surface of most paintings can be seen using ultraviolet rays. In this copy of Cranch's painting, the ultraviolet makes the varnish layer fluoresce. Dark regions show areas that have been retouched or painted over. In the third portion of the page, three images of infrared rays graph, a colored painting, and the same painting in black & white are shown with the following text: Interpreting infrared imaging The penetrating power of infrared most often uncovers preliminary sketches. But infrared imaging can also reveal surprising changes in the development of a work of art. In this self-portrait by Judith Leyster about 1630, the infrared image reveals that the artist originally included a portrait of herself on the easel. But later she changed the portrait to a musician. In the fourth portion of the page, three images of X-rays graph, a colored painting, and the same painting in black & white are shown with the following text: Interpreting X-rays X-rays can reveal the creative process at work. In this portrait of Pope Julius II, painted by Raphael in 1511-1512, the X-ray image shows a pattern of crossed keys on the wall behind the seated figure. The keys do not appear in visible light. Because oil paints are opaque to visible light, the artist probably simply painted over the keys.