Incredible, mind-blowing technology is being used in movies these days that convinces you you're seeing something that's not really there, as this series of back-lot scenes from TV-shows and movie sets reveals.
From an entertainment standpoint, I think all this is truly marvelous. I love how they can simulate anything, any location, any situation using green-screen shoots overlaid with computer graphic illustration (and other such technically devised illusions). But this is also a cause for concern if this grand technology were ever employed nefariously in an effort to deceive people on a wide scale — e.g., to make them think they are seeing, let's say, something menacing or enticing in the sky.
Don't get me wrong. I am happy to see these amazing advances in technology which allow us to expand our ability to imagine. I'm just a little leery about the potential for its misuse. In any case, sit back and enjoy a few minutes of cinematographic magic.