“I met Alex Garland [28 Days Later], the writer/producer and main creative force behind Dredd 3D early on and helped him out on some ‘pitch-vis’ to get the it green lit,” states Visual Effects Supervisor Jon Thum who was recruited to help bring Judge Dredd, a British comic book character who serves as a futuristic law enforcement officer, judge, jury, and executioner, to the big screen again. “Executive Producer Michael Elson contacted me with a plan to start a new Prime Focus VFX facility in London; the film allowed us to effectively build a new VFX facility from scratch, growing from a few people in a small office to over 200 in our new building on Bucknall Street.” Garland was the key figure in the pre-production. “Our Art Department, led by Neil Miller, was involved working with Alex to develop concepts and designs for the film even before Pete Travis [Vantage Point] was on board. When Pete did come on board along with the DOP Anthony Dod Mantle [Slumdog Millionaire] and Production Designer Mark Digby [Never Let Me Go], the group of us sat through all kinds of mood reels and reference that we’d prepared to nail down the look and feel of the film. It was a great collaboration.”
“We looked at a lot of reference and mood reels – slo-mo footage of every description, the scale of big buildings /objects, falling bodies, shoot-outs, tracer fire, and car chases,” states Jon Thum when discussing the visual research conducted for the project. “For Mega City One we looked at brutalist architecture, big cities like Sao Paulo, and Eastern European tower blocks.” A script-to-screen production model was adopted for the action thriller. “The film had to be made for a relatively low budget, so it had to be done in a clever way. The involvement of Prime Focus at such an early stage meant we could help the filmmakers plan Dredd 3D with visual effects in mind. We were there on recce, on set throughout production and through post. At the end of the process we had our stereo post conversion departments convert the mono shots, but they were also utilized to extract more depth out of a number of key stereo shots using a similar process.” Having one main setting made the process less complicated and expensive. “It’s cost effective in terms of budgeting the visual effects because you can reuse assets on multiple shots; it was planned that way to make the film work for our budget.”
“The most challenging aspect was the fact that the film was shot in native stereo,” remarks Jon Thum. “The level of difficulty is much greater, especially at the start and end of the pipe. The camera tracking needs to be much more accurate, paint and roto is much harder; then at the end compositing is harder. The problem is that any work you do on one eye needs to match exactly the integrity of the stereo in the other. It needs sub-pixel accuracy to work. CG FX work can also be challenging because you can’t rely on 2D tricks to help them out.” An effort was made to ensure that the 3D effect aided the storytelling. “We had a creative DOP on-set and he wanted to experiment. We did a lot of research and looked at all the rules there were. We threw away that rule-book and tried some different things. We used test shoots and stereo previs to get an idea of what would and wouldn’t work, especially as we hadn’t seen this genre of film in stereo before. We knew we had some particular shots where it would be good to push the stereo and have it more in the audience from a storytelling point of view, in particular the slo-mo drug POV effect, and we spent time adding depth and layering to those shots.” 90 percent of the 650 visual effects shots were handled by Prime Focus World. “In the final days of the edit, the VFX volume grew, so we assigned some additional work to Baseblack and The Mill; they were people we knew and trusted.” The VFX facilities tended to work independently of each other. “There was not much sharing; only a few shots that Baseblack did FX work on in one of the slo-mo scenes. We applied the final look to those shots at Prime Focus.”
“The biggest challenge was building real-flow into our pipeline, getting it to work properly with our then Maya-Mentalray pipeline,” says Rudi Holzapfel. “We had lots of problems initially, but we did eventually solve them, probably through sheer persistence. The other challenge was making a soft-body behave the way we wanted to. There was a scene when one of the guys, a rather big fellow, gets shot by Dredd and when the bullet enters his naked upper body, the whole thing was supposed to wobble and react in a specific way to the impact; that took a lot of trial-and-error until we figured out a way to control the simulation to the degree necessary.” Holzapfel remarks, “We didn’t so much replace backgrounds as we did marry several plates together. Sometimes this was based on green screen, but a lot of it was roto. On some of the blood-simulation shots we had three layers, distant background, mid-ground with some poor victim and some special effects guy creating wind, smoke, sparks etc. and finally a foreground. To compose the shots we also mirrored backgrounds and mid-grounds at times, re-sped things and dramatically resized the foreground to fit with productions redesign of the final shot.”
“We had several briefing meetings at the edit suite,” states The Mill Visual Effects Supervisor Sara Bennett. “Alex [Garland] was clear about what he wanted to achieve visually for the film which was great as it made the process smooth.” The British VFX facility handled a dramatic 3D moment. “The Zwirner Face [Jason Cope] Melting Sequence was definitely our biggest challenge; we had quite a quick turnaround on the sequence so we had to work in a methodical way. What we needed from the clients was sign off of the key effect stages so that we could move ahead with the complex work without having to keep making changes throughout the process. We achieved this by doing a postvis of the sequence and choreographing all the key points and getting sign off on this before moving ahead to the point of no return!” A pre-production tool was essential in making the visual effect believable. “Creating previs was essential for this sequence; it gave us timings and direction which was needed for the shoot. This gave the actor something to work with and helped us plan ahead with what we needed to create the effect.” Practical and digital effects had to be seamlessly augmented. “We quickly realized that to make this work we would need to do a full CG takeover at some stage during the sequence so we had a 3D scan done of the actors head as well as taking a lot of hires stills. Luckily the action was localized only his head so the CG never went below his collar line. We then mimicked the lighting from the scene using HDR's from set.” The visual effect needed to be accommodated for the 3D cinematic environment. “There was so much going on in the shot that we kept the 3D subtle. What we did do was push the depth on the burn through. We achieved this by creating a lot of skin/fat and muscle layers right through to the skull, which gave us the ability to push the 3D depth.”
Production stills © 2012 Lionsgate Entertainment.
VFX images © 2012 Lionsgate Entertainment. All rights reserved. Images courtesy of Prime Focus World, Baseblack and The Mill.
Visit the official websites for Dredd 3D, Prime Focus World, Baseblack and The Mill.
Many thanks to Jon Thum, Rudi Holzapfel and Sara Bennett for taking the time to be interviewed.
Trevor Hogg is a freelance video editor and writer who currently resides in Canada.