This is the art of Hwang Seon Tae, it's like an acrylic panel with a dull grey architectural composition. A picture has to be taken in order to see the shadows and the 3D image. I took the picture together with ten more people, and once I was done, I saw a handwritten tiny sign around the stand corner "do not take pictures", which I think was a joke.....From Los Angeles Art Show 2017.