Movie magic has existed since the first film of a train entering a station was shown on a big screen. Legend has it that the 19th-century crowd ran from their seats, believing that a real train was about to crash into them.
The advent of computer-generated imagery (CGI) has only added to the tricks up a director's sleeves. Relying on these techniques can make an actor's job even harder, as they must imagine the scenery and co-stars at times. Here are 10 of our favorite examples of how different a scene can look before and after post-production.
1. The Avengers
Chris Hemsworth looks so earnest as he pretends to be rocked by an explosion—all the while he's simply staring at a blank green screen.
2. The Life of Pi
Suraj Sharma did a phenomenal job as Pi Patel. The character was stranded on a lifeboat with a very angry tiger for many days. The effects were so realistic that many viewers thought that Sharma did the scenes with the tiger.
In reality, the actor relied on a blue stuffed animal to take the place of the tiger.
3. The Monuments Men
This incredible movie is based on the true story of a World War II platoon tasked with recovering stolen art from the Nazis. Director George Clooney used an old trick to replicate a long mine shaft in the studio.
Godzilla movies have always relied on special effects to achieve destruction on a mass scale. Now, with the help of CGI, they don't necessarily have to build miniature towns to destroy.
This film about a dystopian future featured very advanced robots. Alas, they were too advanced for the filmmakers to build, so they had to be added digitally (with the help of an actor covered with sensors).
6. The Chronicles of Narnia
Here is a view of a blue screen used to replace the background in the epic fantasy franchise. Usually directors use the better-known green screen, but the screen can actually be any color (so long as that color doesn't exist in the part of the shot that is to be replaced).
7. Game of Thrones
Khaleesi and her dragon don't seem as intimidating during filming. That's largely because the dragon is a simple rod covered with a cushion and green fabric. Emilia Clarke and the visual artists of the show bring the somewhat silly dragon stand-in to life.
8. The Great Gatsby
Recreating New York City in the Roaring '20s requires a lot of cash—so much cash that it is easier to digitally create much of the city behind a few vintage taxis and fabulously dressed actors.
9. The Dark Knight
Director Christopher Nolan generally eschews digital effects, but to show Harvey Dent's transition to Two-Face, he needed a little help from a computer. The result was a disturbingly realistic charred face with sinew and bone showing through.
10. Oz, the Great and Powerful
Here is another example of a blue screen being employed, this time to show James Franco as Oz setting a hot air balloon down in the middle of a roaring river. Franco's top-notch acting skills help complete the scene.