Lenticular cloud and zebra. (Photo by National Geographic)

Street artist JR poses in front the Louvre Pyramid in Paris, Tuesday, May 24, 2016. For his latest bold project, street artist JR is creating an eye-tricking installation at the Louvre Museum that makes it seem as if the huge glass pyramid at the heart of the courtyard has disappeared. (Photo by Francois Mori/AP Photo)

Ukrainian artist Oleg Shuplyak masters the optical illusion in his incredible scenic oil paintings.