Recent technology has changed filmmaking forever - but special effects are now so seamlessly done that sometimes you can't even tell that the crew didn't just pitch up with their cameras and record real life for two hours.

Here are ten surprising ways that tech has been used to create recent films:

1. Gravity's sound effects were recorded underwater

How do you make space sound like space? Go underwater. The Oscar-winning sound effects team on Gravity created every sound you hear in the film from scratch, often recording underwater to get that fuzzy, echoey clonks of space engineering just right. They also recorded real live NASA staff saying real life NASA things for that added element of authenticity.

2. Godzilla is half man, half CGI monster

Okay, so maybe not quite half and half, but while the team behind this year's Godzilla reboot created most of the monster using computer animation, they also took inspiration from the original by putting Andy Serkis in a motion-capture suit to add some man-in-a-monster-suit authenticity to certain scenes.

Godzilla

3. Converting a 2D film to 3D is "like mowing the lawn with a toenail clipper"

So says 3D's biggest advocate, James Cameron, of the process of turning Titanic from 2D to three. It's not a case of find and replace, it's a manual labour of love. "It is a mind-numbing process of creating depth subjectively," he says. "I sit there with the jog wheel and look through the movie frame-by-frame and make notes on depth. That should be closer, that should be further back, there's not enough full depth here... It's like mowing the lawn with a toenail clipper."

4. Pacific Rim's VFX were based on a 200-year-old painting

Although it's a film about massive robots fighting giant monsters, Pacific Rim's director, Guillermo del Toro, had very specific reference material for the animation team: Goya's 19th century painting, The Colossus.

The fight scenes in the film were completely computer generated, but animation director Hal Hickel told us, "That was first image he showed us, The Colossus by Goya, and the first words del Toro spoke to us about Pacific Rim were 'operatic' and 'poetic'." Followed closely by 'smashy' and 'fighty', presumably.

Pacific Rim

5. Loads of the sets in Wolf of Wall Street were computer generated

You'd never know it while watching, but a whole heap of the shots in The Wolf of Wall Street were built and added to using computer generated images. Don't believe us? Check the video out.

6. Virtual reality filmmaking is so effective they make you sign a waiver before you can have a go

As our own Michael Rougeau found out, wearing Oculus Rift to scale an 800ft virtual wall is so vertigo-inducing, you have to sign a waiver before they'll let you try it out. Makes 3D seem a bit tame, really, doesn't it?

7. Sometimes going low-tech is the only way to get things done

When working on Submarine with Richard Ayoade, the special effects geniuses as Framestore created a digital credits sequence which they then shot out to 35mm film then brought it back to digital to achieve exactly the right kind of grain. "We weren't applying film grain digitally," executive producer Simon Whalley explained to us. "We were putting film grain on by shooting it out to film and then putting it back in. Richard's very very particular about that. He can really tell the difference."

8. The VFX team invented completely new tech for Gravity

Because the tools needed to film Gravity in exactly the way director Alfonso Cuaron envisaged didn't actually exist, the visual artists at Framestore effects house literally made new ones. These included a 3D scanner that creates models by taking 360-degree photos of an actor, and inventive new lighting solutions.

Two more fun Gravity facts for you: 1. A team of 40 people worked on only simulations of cloth for over a year to make sure the space-suits looked right. And 2. if the filmmakers wanted to render the entire film on just on machine, they'd have had to start it in 5000 BC for it to be ready today.

9. A holographic Star Wars could happen

Help us George Lucas, you're our only hope - it's not just Leia who can play the holographic game. According to special effects maestro Dennis Muren, "If there is a way in the future to do a hologram version [of Star Wars] and the fans want it then it should be done. You don't just want to stop making movies and keep releasing old ones, though. These releases should be seen as a supplementary thing."

Star Wars

10. The Star Wars Blu-rays used 70s sound techniques

When the Lucasarts team was busy remastering the original Star Wars trilogy for the 2011 Blu-ray release, audio specialist Matthew Wood not only unearthed the original production rolls from 1976. "These were the rolls that were used for the original dialogue recording and the entire production recording that were done on the set," he told us.

"These [production rolls] had only been played once, the first time they were used they were transferred to magnetic film back in 1977 and that was cut. So I got to take them and retransfer them into the computer and with the highest quality analogue to digital converters I could actually re-sync these back into the original picture. That is one thing that is new on the Blu-ray. It's amazing."