Feedback

Tag cloud

What's your question?

By: [ Admin ] Asked from India

How was the zero gravity effect achieved in the opening shot of Avatar?

Was it wires? Or was it a set in a free-falling jumbo, or were they all CG. Spill the beans. If you worked on that shot or know who did it, ask them to post here please.

Add comment viewed 990 times Latest activity 7 months ago

NN comments
julian
-

I still don’t have a clear image in my head what this rig looked like and how it worked. We need some physics explained (in layman’s terms). Or even better a diagram. I have searched the net, but nothing comes up.

or Cancel

8 answers

  • 3

chas jarrett

The spinning rig I've seen stunts use on a couple of films is a metal hoop about 20 inches across which is strapped securely to a persons hips (like a tight hula-hoop). This is connected to wires (one on each side) so the actor can be lifted and can tumble forwards and backwards. The hoop has an internal revolving hoop which allows the actor to also rotate around their local Y-axis. This arrangement means the actor can tumble and twist - plus the wires (or crane arm as mentioned) which can be operated to give a floaty motion. It's a pretty sizable contraption though - so a bit more work to paint out - it gets in the way of loose clothes - and it hurts like hell to wear! Chas.

NN comments
or Cancel
  • 3

owen_87

Interview with stunt master Garrett Warren:

"He left it up to me to try and design a new way to shoot zero-G weightlessness in outer space — which is how the movie starts. We wound up getting an apparatus which is called a spinning ring, and we wound up using it with different kinds of rigging techniques — sometimes flying it by wires, sometimes sticking it on the end of a metal arm like a yolk and a parallelogram — so that we were able to really create what would look like weightlessness in outer space. It's somewhat of a difficult process to go through to actually get on that Vomit Comet. We first ended up doing that zero-G plane that flies out of Burbank. Also, you only have a certain amount of time where you can film it, and you only have a certain amount of space. Jim didn’t want to be limited with his space because in the movie you see there are hundreds of people on this huge space shuttle, and you want to be able to have as realistic of a set as possible and have all these people floating weightless on your set so … it’s the first time it’s ever been done and performed this way. That’s why it was so groundbreaking. We had this ring that someone could move 360 degrees in all directions. We could fly them up, down and around — that’s what helped give us that feel of what weightlessness in outer space looks like."

NN comments
julian
-

thanks for this – although I’m still not clear what he means. Was it centrifugal force. That would mean a huge set and cameras and everything all spinning.

hugh_gid
-

I have to say, I’m confused. Like Matt said, centrifugal force (okay… centripetal acceleration) would add more apparent gravity rather than less. To get none at all, you’d have to build a massive spinning set that gave you 0G at the top, but would then crush you with 2G at the bottom of the spin. It would not be pleasant, and would be prohibitively massive.

or Cancel
  • 2

mattwbp

Julian - Centrifugal force is outwards from the point of rotation, so this wouldn't be used to create a low gravity environment - the actors would get sent flying into the walls like one of those fairground rides. :)

Owen's posted quote from the stunt master Garrett Warren isn't very precise, though possibly because a magician doesn't reveal his tricks. The impression I get is that they used a complex set of rigs and crane arms, some with motion possible in every direction to create the impression of low gravity movement - then painting the rigging out in post.

The Vomet Comet they mention is a plane that flies to a high altitude and then dives very quickly for around a minute. The occupants experience low gravity for the duration - so I'm guessing they filmed a load of this with similar movements for reference and then attempted to match it with the rigging.

I'm no expert at practical stunts, this is just the impression I got of Owens quote. It'd be nice to be able to add this as a comment below yours on his answer.

-Matt

NN comments
julian
-

thanks Matt, I’m less in the dark now than I was – just a little ;)

or Cancel
  • 1

benf

After a second viewing, I believe that the clothing worn by Jake and the medical staff may be CG too. The sequence of shots is so quick that it makes it difficult to know for sure. Anyone know?

NN comments
or Cancel
  • 1

paddy_95

I recently toured the vfx house that did those shots - certainly the environment was CG. Not sure about the people in the bg. One thing I did notice was how many hours of CG work their system had logged for the shots. OMG! I can certainly see why a) Avatar had such a huge budget and b) why it all looked so great.

NN comments
or Cancel
  • 1

alex capecelatro

If anyone is interested, we are planning a zero-g flight on the vomit comet to commemorate this very scene. We are extremely excited because Jim Cameron will be joining us on this flight and talking abut the filming of the scene. If you're interested, seats will be auctioned, and you can contact me to find out more info. ac@alexcaps.com

NN comments
julian
-

Thats so cool! I wish I had the cash. How many seats will there be? It would certainly be great to hear some details about the shot from the man himself. Perhaps after the flight, Jim can get a login on vfxoverflow and post an answer here ;)

alex capecelatro
-

There are only a couple dozen seats and they’re going quick. Jim is giving a special lunchtime talk about this. Let me know if you’re interested.

or Cancel
  • 1

chris watts

Just wait 'till you see the zero-g work in Alfonso Cuaron's "gravity". If all goes as planned, it will blow away anything that's ever been done before!

cw

NN comments
julian
-

Sounds cool! I see you are supervising too. Really looking forward to it!

I can imagine it will be one of the few movies that works in stereo. (is it stereo?) I haven’t seen much stereo I like at all but I imagine there will be lots of slow graceful floaty stuff hanging in the theatre space.

or Cancel
  • 0

shawn mclean [ Editor ]

- There is no such thing as a centrifugal force. There was and people still calls it centrifugal force, but scientist disregard that now. It is called centripetal acceleration, there is no outward force at all. http://en.wikipedia.org/wiki/Centripetal_force

ps. Sorry, I cant make comments :(.

NN comments
hugh_gid
-

You obviously don’t read XKCD then, Shawn! http://xkcd.com/123/ I would say that, while it isn’t a force the standard sense, it appears to people and objects in the rotating system as a force, and people do generally know what you’re talking about…

hugh_gid
-

Oh, and as for leaving comments – once you’ve got a reputation of 50, you can leave comments on questions and answers other than your own…

julian
-

that xkcd cartoon was funny!! – but getting back to the topic, we need a clear description of what that spinning ring thing looked like and how it worked. A lot of people end up on this page from google – we mustn’t disappoint ;) Surely someone here has a friend of a friend who knows. Otherwise we’ll have to conclude it was all wires and a rotoscope army.

or Cancel

Question's Contributors

Related Questions