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FireflyMore on the Visual effects used in Serenity - Vfxblog.com Interview - Spoilers
Saturday 8 October 2005, by Webmaster
Rhythm & Hues’ Bud Myrick on ’Serenity’
Rhythm & Hues Studios visual effects supervisor Bud Myrick speaks with vfxblog about Rhythm’s digital work for the generator sequence in Serenity.
Interview by Ian Failes
Can you give me an overview of Rhythm’s contribution to the film?
B_myrick_1We mainly did the set extensions for the generator sequence at the climax of the film. We were contacted by Zoic, who were the primary vendor, to see if we could actually design and create the generator.
What work was involved in that sequence?
For the sequence the actors were shot on a greenscreen in a partial set. What they wanted to do was to take that set and extend it to make it huge and imposing, so that everything about it was threatening and scary. We had to make a big, vast hole filled with spinning machinery where (a) the fall would kill you and, if it didn’t, (b) you’d get smashed to bits by all the spinning blades. It needed to look impressive and scary and give you a sense of vertigo once you go over the edge.
Did you also previz the sequence?
Not really. They shot it and gave us the plates. They didn’t have a design that they were happy with yet, so they asked us to come with a design as well. Unfortunately, since we came in after everything was shot, we didn’t have the full handle on things that we usually like to have. We didn’t quite have the set data we’re used to working with, and things like that. So we didn’t really get to previz, although I did build some crude mock ups of the generator to get Joss’ feedback in terms of depth and scale and the working parts to it. As we were designing it I built some rough models in Maya.
What made up the final shots for the generator sequence?
Well, certainly the first trick in any shot like this is getting rid of the greenscreen itself. There were a lot of light fixtures on set and, to add an extra challenge, as part of the set there were chains hanging from the truss work. The actors fall into these chains as part of the action sequence. So we had these tiny chains over a greenscreen with practical light fixtures and lens flares through the chains that we had to rotoscope out! Our team in India did the greenscreen pulls for us and all the rotoscoping on that. They did a fabulous job. All the plates were really complex in terms of what had to be pulled.
The second trick is tracking the camera. It’s a moving crane shot with a lot of interesting moves. Since we weren’t on set we didn’t have any real hardcore set data. We had lenses and some rough camera heights. Normally I like to survey the set and get very accurate dimensions from that. We had some photographs of the set, but no real dimensions other than some general blueprints which were really stage layouts. So we had to make some guesses. The end of the generator shaft hooked up with the bottom of the practical set piece, which means we couldn’t have any errors in the tracking. We’re literally looking up and extending the set piece with these huge dynamic camera moves.
Those were the first two steps and pretty challenging ones at that. From there we created three dimensional elements of the generator itself. Joss basically said he wanted it to look scary, but that it also should make some sense in terms of what the parts are, not to put things in just to look cool. They had to make sense within this world that has some sort of logic to it. So we had to design something that was of course make believe but still had some logic behind the pieces. We had these huge generator arms that spun, energy fields and lots of shafts and fans for cooling. There were a lot of things spinning as you looked down. Nick Pugh, one of our production designers, and I worked together on the design of the generators. One of the cool things Nick came up with was splitting the bottom to a manifold that had three additional shafts that came up. So, really, you never see the end of the shafts. They just seem to keep going up forever and ever. We really tried to add that huge element of danger and vertigo to it.
Once we got the design sorted out, I gave Wei Ho, our modeler, the overall design as a Maya file and let him run with that. Wei really contributed a lot in terms of the detail. We gave it things like staircases down on the lower level and platforms, which helped give it some scale. It was literally so far away and so big that it was hard to get a real cue about how big it was. We wanted to add some things that you could visually latch onto. When you see these staircases, it’s very subtle, but people know the scale of a stair case. So when you see how small it is in the distance, and that’s just on the lip of this thing, which is still 150 feet away, you get an idea of the scale.
Rough composite with model.
The other thing was that Joss wanted to see some generators extending off in the distance and never see the end of this thing, so that it would seem that it could just go on forever. We did that with lighting. We of course had a finite number of generators, and each generator had a lot of geometry. So we tried to reduce that as we went further back, and also have the light fall off in the distance. I used red lights like you’d find on power lines by an airport or on tops of towers for airplanes. I had these little red lights that just went off in the distance. Once the lighting fell off from the other generators, you still had a cue that this thing might just keep going. We used some perspective and fall off to insinuate that this thing never ends!
For modeling we used Maya, but everything else was done with our proprietary tools. We used our in house animation package, Voodoo, to animate it, then Ren, our rendering tool to light it. Because we were attaching to a real set, the lighting had to be incredibly believable. Greg Yepes and Dan Lazarow did a great job of lighting this thing, using ambient occlusion to give it the reality of the way light falls off and interacts with surfaces. We used a minimum of amount of ray tracing. There were some elements that get reflections like the generator shaft. Lopsie Schwartz, our texture painter, had a real challenge getting the scale into the textures, which were made up of concrete and steel. So one of the things I asked Lopsie to add were things like signage and numbers and painted decals and elements, and also to give it a worn look. This was so you could see where the paint is and where section numbers had faded away.
In one of the shots Joss has Mal knock a case over the edge. I tracked the case that was on set with our CG case. The real case falls about five feet on set, so I just picked up the motion of the case and kept it going and let it going for 200 feet until it hit one of the generator arms and smashed to bits.
There’s this bridge at the end of the generator sequence which finally comes out so Mal can walk back across. Joss wanted some sort of interesting bridge to come out - not just one with the usual hydraulics. So I came up with a rotating thing with hydraulics on it where each step folded into each other and rotated as it unfolded and then locked into place. That gave it some extra interest as the walkway comes out. We designed it with a wire mesh so that you could still see through the mesh how far you would fall down if you went off the edge of the walkway.
Another thing in that scene, which was a cool thing, happened in the compositing world. When Mal was on the greenscreen set he was walking on a rigid ramp, but this thing is on a shaft and there really should have been some give to it. So I had the compositors take the final rendered image of it and the greenscreen of Mal and give it some give and rotation as Mal stepped on each of the steps on the bridge. This really integrated the actor into the CG environment so that he was having an effect on the CG world. It’s a very subtle thing but it’s amazing the difference it made from seeing the rigid thing that didn’t really look like it would be rigid. When we added the interaction from each step from his weight it just made it work. There’s a lot of subtle things in there and they’re all designed to make you just buy it.
Jonathan Robinson was the head of our compositing team, who all did a great job. The greenscreens were pretty crazy and it was a challenge for them. The really did a great job to interact the live action with the CG.
Were there some other smaller sequences that you worked on?
We did do the holographic inserts for the funeral. I designed these, then worked on another project, so Dan DeLeeuw supervised the funeral sequence. We also replaced a bow and arrow thing. In the screenings, people thought that seemed a little low tech for the environment, so we replaced it in several shots. Nick Pugh again did an amazing job of coming up with tons of high tech crossbow designs to replace the one that was on set. Dan DeLeeuw supervised that and the funeral sequence with a small crew.
Joss Whedon obviously seems to know his way around visual effects. Did that make it a different experience for you?
You know, this is one of my favourite projects I’ve ever worked on, because working with Joss was just great. He came in originally and really knew what he wanted. When he came back we showed him some things and he liked what he saw from the get-go. So I think we earned his trust early on. From that point, it seemed like everything was always a progression. We never went down a path where Joss said, ’No, no, no, we’re not doing the right thing. We need to go back and try something else.’ I think every step of the way was a forward progression.
Joss just has this great energy. He’s a very intelligent guy and he’s got a lot of enthusiasm. We were sitting in dailies one day watching some miniature stuff. I was right behind Joss and Lisa Lassek, the editor. This footage was pretty cool - a five foot miniature of the Serenity ship crashing - and Joss turns to Lisa and goes, ’We’ve got the coolest fucking jobs in the world!’ So that sort of energy and enthusiasm really trickles down. It kept me excited about it, and with me enjoying the job the crew said they could feel that energy from me as well. There are heaps of Joss Whedon fans here at the studio and a lot of people went, ’Oh, I wish I was working on that!’
Joss is also very witty and a lot of his comments were incredibly fun. He would say things like, ’That’s a little too fabulous.’ We really enjoyed these creative criticisms. Lisa Goldberg, our producer, loved writing down Joss’ notes because they were always kind of interesting. Joss really had a feel for what he wanted. There wasn’t a lot of fishing. He trusted us to give him what he wanted and he was always enthusiastic and excited about it, which made for a great working relationship. It was actually quite easy working on the film. Like I said, it always felt like it was almost always a forward progression, not having to go back to something. The trust made things easier because there wasn’t a lot of second guessing. He’d tell me what he wanted and trusted me to bring back what he asked for, which I tried to do every time.
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