It isn’t, and that’s the beauty of it. When I first started learning lighting as a photographer, it was explained to me that great lighting will never let the viewer catch onto the fact that the light is artificial. Now with CGI the same thing is true.  Did you assume this popsicle was real? I hope so, because that would mean we’ve done our job well. As Peter adds CGI elements to our photos/videos we’d like to always leave the viewer wondering what was real and what wasn’t, wondering “how did we do that?” and always wanting to see more!