6 Mind Blowing Special Effects You Won't Believe Aren't CGI

They had huge water cannons hiding outside the windows, firing somewhere between 3,000 and 4,000 gallons into the set as DiCaprio stood there, soaking wet.

Don't think DiCaprio got to have all the fun, though -- if there's one scene that screams "CGI," that would be the iconic hallway fight scene where Joseph Gordon-Levitt climbs up walls and runs through the ceiling as if gravity had taken a break:

But nope, that's all real, too. Doing the scene with wires and erasing them digitally would have been too easy, apparently, so Christopher Nolan actually built a 100-foot-long rotating hallway and locked down the camera to rotate with it, effectively making it look like the actors were defying gravity.

So what about when DiCaprio and Ellen Page are sitting in a cafe in Paris and he reveals that she's actually dreaming, and then everything explodes around them?

You'd think from how cool the actors seem in that scene that they were actually sitting comfortably in front of a green screen, but that explosion is real -- the filmmakers put air cannons inside the cafe and in the stands across the street, then blew everything to shit around DiCaprio and Page. You can see their "Oh shit" faces here:

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That's a real photo of Cruise on top of the Burj Khalifa in Dubai, the tallest man-made structure in the world, during the production of Mission: Impossible - Ghost Protocol. If you've seen the film, you know that Cruise climbs the building -- what you might not be aware of is that he literally climbed the damned building.

When the production team saw that the script called for Cruise's character to perform some stunts outside the Burj Khalifa, they immediately started working on re-creating part of the building inside a soundstage, which they could then digitally combine with the real thing, because they just assumed that no one would be crazy enough to actually want to climb it. It took a single meeting with Cruise to prove them wrong -- turns out he'd had his eye on the building for some time and wanted to make it his bitch.

As usual, Cruise insisted on doing this without any stunt doubles, even though shooting the scene required being strapped into a painful harness and hung like a freaking pinata against glass that became so hot that it was impossible to shoot under direct sunlight. The film crew set up camp in the unfinished 123rd floor of the tower and had to remove a bunch of windows so they could stick out all the necessary equipment to film Cruise's stunts and, you know, keep him alive and stuff.

One stunt even involved running down the face of the building in order to stealthily break into one of the floors ... because nothing says stealth mission like hanging off a building in the middle of the day.

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Alien: Resurrection got a lot of crap for its use of (bad) CGI aliens, when in fact most of the movie was done with good old-fashioned puppets and model spaceships. For example, the gruesome scene where the human/alien hybrid is sucked into space through a tiny hole in the spaceship ...

... was done entirely on set by creating plastic replicas of the creature and then literally pulling them through a hole.

However, the coolest moment in the movie needed no puppets or effects at all. In one scene, Sigourney Weaver is playing basketball in the ship's gym when Ron Perlman and his posse show up and start giving her shit. Weaver proceeds to kick their asses and walks away -- but not before performing an impossible over-the-head blind shot resulting in nothing but net.

That's the real thing there. Originally, the director wanted to fake the shot using CGI or having someone else drop the ball from above, since he wasn't looking forward to doing 200 takes until they got one right, but Weaver insisted on doing it herself. The crew went along with it, the whole time assuming that they'd have to eventually CG a ball in during postproduction. But then, to everyone's surprise, Weaver got it on her sixth try.

In fact, in the unedited footage, you can see that Perlman almost blew the entire shot by breaking character and going "Oh my God" after the ball goes through. That's why the movie cuts away to a different reaction shot so quickly after that part.

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You probably know that Stanley Kubrick's 2001 was made in an era where CGI as we know it didn't really exist, but you're not conscious of it when you watch the movie. You take it for granted that, for instance, a zero-gravity scene could be done pretty easily. And it could -- you just computerize that shit. But in 1968?

The movie's effects are good enough that you don't think of them as effects at all. And what Kubrick didn't have in technology, he made up for with cleverness and trickery.

For example, the classic scene with the astronaut taking a zero-gravity jog around the spaceship in one continuous shot was made possible not through postproduction effects, but thanks to what was basically a giant hamster wheel:

This massive centrifuge set would rotate while the camera remained fixed in one position, giving the appearance that the actors were defying gravity. And speaking of which, what about the famous shot of the pen floating inside the Pan-Am shuttle? It looks so real that most of us never even questioned how Kubrick did it.

The same effect that today would cost thousands of dollars in CG was created with one pen, a large sheet of glass and a piece of two-sided tape. That's it. They put the glass on a frame and rotated it slowly in front of the camera. When the flight attendant goes to pluck it out of the air, it was just a matter of unsticking it from the glass.

Even the trippy "star gate" part at the end was made without CGI -- because, again, that wasn't a thing yet. If you've ever been to a laser show, you're familiar with the effect:

This was achieved through something called slit scan photography, using nothing but two sheets of glass, some backlit paintings and a camera that moved backward and forward on a track. The first glass is completely black except for a small slit at the center, while the second glass has the paintings on it: As it moves, the camera records the painting through the slit, resulting in the trippy effect.

Related: 5 Everyday Things That Go Totally Nuts in Zero Gravity

Seeing one of the busiest cities in the world all empty and quiet is pretty unnerving -- but what the movie doesn't show you are the many pissed-off commuters screaming just out of frame. As you've guessed by now, they did this without any postproduction trickery whatsoever, and in fact these scenes were only made possible due to a downgrade of budget and technology.

Instead of shooting the movie with traditional film cameras (which would have taken hours to set up for every shot, meaning they'd have to ask permission to close the streets), the filmmakers decided to go with a bunch of relatively cheap Canon XL-1S digital ones, which they could basically just point at Murphy from different angles as he walked through London at the wee hours of the morning, when crowds were limited to workaholics going to work and alcoholics stumbling home.

Thanks to the cheaper cameras, they were able to complete the entire sequence by taking over the streets a few minutes at a time, kindly asking angry commuters to either be patient or take alternate routes.

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Even U.S. audiences with their famous aversion to doing any reading at the movies were captivated by the epicness of the opening crawl, which is kind of impressive when you consider that you sort of have to squint to read parts of it if you fall behind. These days, there's probably an app that can make any random snippet of text fly off into space in classic Star Wars fashion, but back when George Lucas was making the first movie, you couldn't just type the words into a computer and be done with it -- at least not with the budget they had.

No, Lucas had to think of another way to make words float in space without relying on fancy technology. As we've mentioned before, Lucas got the idea from the old Flash Gordon adventure serials from the '30s that he totally didn't rip off, so he needed to put his cinematic knowledge to use and research the proper way to get the titles to move like that ...

... or, you know, just tilt the camera and slowly move it across a printed plate on the floor, whichever. Apparently it wasn't very fun to do, because it took a lot of tries to get that smooth scrolling effect we've come to expect from these films -- not to mention that even when they got it down perfectly, they'd have to do it several more times for the German, French, Spanish, etc. releases and such. We have no idea where the original plates are now; probably the same LucasFilm warehouse where they keep Peter Mayhew.

Still, there's a charm and an undeniable historic significance to this completely analogue method that a digital version could never reproduce -- so, naturally, Lucas already went back and replaced it with a computer version in later releases.

To see Cracked do George Lucas one up, watch our Adventures in Jedi School mini-series.

David is a freelance writer, feel free to follow him on Twitter or check him out over at Film School Rejects, where he is a regular contributor.

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