Alain Bielik chats with Bill Taylor and Syd Dutton of Illusion Arts about the invisible VFX for Casanova.
Two hundreds years after he passed away, Giacomo Casanova (1725-1798) is still remembered as the worlds greatest lover. Contrary to Don Juan, another legendary (but fictitious) womanizer, Casanova really existed. He lived an extraordinary life of adventures, traveling throughout Europe and seducing extraordinary number of women. When his scandalous behavior cost him five years of imprisonment, he managed to be the first prisoner ever to escape Venices notorious jail! The life of this character extraordinaire was turned into a movie as soon as 1918, and many different versions followed. Casanova (released by Touchstone on Dec. 25) is the latest interpretation of the myth. In the title part, Heath Ledger adds his name to an impressive list of actors that includes Marcello Mastroianni, Tony Curtis, Donald Sutherland, Peter OToole, Richard Chamberlain and even Bob Hope.
Searching for maximum realism, director Lasse Hallstrom elected to shoot the movie in Venice, on the very streets that Casanova had walked. He also wanted to recreate the look of the city in the 18th century in the most genuine way. To this purpose, he called on the expertise of visual effects supervisors Bill Taylor, ASC, and Syd Dutton, co-founders of the 20-year-old Hollywood-based visual effects company, Illusion Arts.
We did over 200 shots on the movie, including 120 shots featuring invisible effects, Taylor states. Most of them required modifying modern Venice into its 18th century look. At first, it seemed like there wouldnt be much to do, as Venice is considered to be one of the best-preserved cities in the world, but it turned out that modern architecture and 21st century elements have crept in just about everywhere. There wasnt time or money to fix everything, nor would have anyone noted the smaller details, so we had to pick our targets.
While supervising plate photography on location, Taylor first noticed that in an ideal world, almost all the windows needed to be replaced. Venice buildings now feature large double paned windows, which were totally anachronistic at the time of Casanova. He also observed that few of the traditional pepper pot Venetian chimneys remained. At that time, every room had its own fireplace, which meant that a house could have 15 chimneys. Now, they all have central heating and these chimneys that used to make up the roofline of Venice have all been torn down. So, where we could, we put them back in.
Illusion Arts assignment also included removing television antennas, anachronistic rooftop gardens and neon lights. Many building facades had to be heavily retouched as they featured exterior plumbing, cables and wires that had been added onto them over the centuries. This process involved modifying the colors of the facades too, Dutton comments. Nowadays, the city has a large palette of colors, but when we looked at paintings from Giovanni Canaletto (1697-1768) our inspiration in recreating 18th century Venice we discovered that the city had a completely different color palette at that time. So, we had to take this into consideration when we created our shots too.
While on location, Taylor took thousands of reference photographs (I wished he had taken 3,000 more! Dutton laughs). On several locations, though, this turned out to be impossible, as many buildings had scaffoldings on them, and some were even covered with tarpaulins Back at Illusion Arts, the plates were treated on a shot-per-shot basis. The first task was to track and to matchmove the plates using Boujou. When the camera move was tracked, lead matte artist Kelvin McIlwain and matte artist Justin Brandstatter created the replacement elements windows, chimneys, facades in 2D using Photoshop. In a few cases, entire buildings had to be replaced in 3D, a mission supervised by Mary Manning and Michael Meyers. At Illusion Arts, our usual tool of choice for 3D is Maya, but, on this project, Mary incited us to use SOFTIMAGE|XSI instead, Dutton remarks. We found that it was actually faster, and that its built-in renderer suited our needs perfectly. We did use Maya to create CG boats on the Grand Canal. The layers were then composited with After Effects under David Williams supervision.
Flying Over A Digital City
A few shots required a full-on 3D build and they were all part of a sequence in which Casanova takes his love interest on a romantic fly over Venice in a balloon while fireworks illuminate the sky. The filmmakers had originally planned to shoot aerial plates for the sequence, but soon discovered that authorities wouldnt allow any vehicle to fly at low altitude above the city. They considered several options, including cable cam and even a balloon, before turning to 3D animation. The principals were shot in front of a greenscreen in a basket, Dutton adds. The city was then entirely built in the computer, either as 2 1/2 D matte painting, or as a 3D environment. In the end, I was glad we didnt have aerial footage. It would have required removing hundreds of neon lights, rooftop gardens, TV antennas, non-period buildings, a huge undertaking since these were all moving shots. On the other hand, a full-on 3D approach enabled us to have complete control over the background. We could then create the highly romantic environment that the scene demanded.
The basic layout of the city was created from a satellite picture of Venice. The photograph provided a precise map of all the canals that Manning was able to turn into a 3D layout. The crew then modeled dozens of simple 3D geometries and textured them with still photographs shot by Taylor, or with painted artwork. Whenever this approach didnt provide the necessary level of detail, the artists went back to the original model and added extra details to the geometry. Our philosophy has always been to first rough out a shot, which allows us to see what the problems are, Dutton remarks. Then, we add detail exactly where we need to and only there. Our approach is different than some peoples approach, which would be to build a huge model and to detail it all out. We try to see the shots on the big screen as soon as possible. That gives us a very good feeling of what is actually needed, much more than by looking at a playback on a monitor. Matte artist Bob Scifo was instrumental in nailing down the final look of the city. He created a matte painting that we later split into planes. It was then turned into a multiplane shot in which several 3D foreground elements were incorporated. We then determined that the all 3D renders for the sequence would be based on the look of this particular shot.
Crafting Nebulous Skies
The skies in the sequence necessitated a long period of research from Dutton. Highly romantic, his first rendition of the clouds was deemed too stormy by Hallstrom. Dutton then opted to test a plug-in developed for Photoshop. Glitteria was designed mainly to produce star nebulas, Dutton explains. I supposed that the nebulas could be reduced to cloud-like shapes. So, I made a large field of these little puffy nebulas for clouds, and this became the basis for all our skies in the movie. I had never thought about using a software to create clouds. Out there, you have all these different plug-ins that have been developed for Photoshop, Maya and others. If youre able to find the right one, sometimes, it can solve your problem. Using this software, I created a palette of diaphanous clouds that we could then use by cutting and pasting group of clouds, and finally by painting on top those.
The flyover shots were made even more complicated by the continuous bursts of fireworks. Illusion Arts shot real fireworks on Independence Day and composited them into the shots. Each individual burst was followed by a puff of smoke that was shot live and added in. Finally, the water in the canals was computer-generated and the balloon itself was created in 3D with a combination of cloth simulation and keyframe animation. In longer shots, the characters were also recreated digitally.
Although the flyover was the most complex sequence of the movie, many other shots presented considerable challenges. One of them featured a huge camera move filmed from a boom arm on Piazza San Marco, the citys main plaza. During plate photography, the crew blocked off the ends of the plaza with greenscreens to hide the tourists in the background and the dredging operation at the waterfront. However, no green screen could be used to block off the long archways that occupied one side of the location. A third of the same building was also covered with scaffolding from top to bottom. Since the passage was open to public and featured dozens of tourists staring at the costumed extras, Illusion Arts had to replace the entire archways with a CG model. Then, the passage was digitally populated using two different techniques. All the costumed characters in the archways were either lifted from alternate takes or are animated cut-outs, Taylor suggests. Since this was a huge boom shot, and no two boom moves are ever the same, lifting the characters was a tough tracking and roto job. We then recreated the part of the plaza beyond the greenscreens and also replaced the clock tower with a CG model, as the real building was covered with tarp when we shot the plate. We then removed the modern boats and all the digging equipment that was visible on the water, and replaced them with CG period boats and a clean waterfront.
In this sequence, as in many other shots, the crowd was increased by adding groups of extras. This proved to be difficult as some shots featured extensive crane moves. Since there werent enough shots to justify creating a crowd with 3D animation a la Massive, Illusion Arts used several approaches. For the shots that were planned to add to the crowds, Taylor shot groups of costumed extras on greenscreen and those elements were later positioned in 3D and composited in live-action plates. For the crane shot of Casanova and his lover Francesca walking to the gallows for his execution, the greenscreen extras were layered in the plaza in some 50 superimposed planes. The crowd layers followed the perspective of the Boujou camera track. Using this technique, Illusion Arts was able to recreate with simple 2D elements the three dimensional perspective shift generated by the camera movement. This 45-second shot actually contains about 25 minutes of film elements!
The end of the Gallows crowd sequence required improvisation from Taylor and Dutton. We had planned to shoot Casanova and Francescas escape from the gallows in the Piazza San Marco, but for various reasons, we ran out of time, Taylor recalls. So, much of the sequence was crafted in post-production. It added more than 50 complex shots to our workload. We first shot the actors, the gallows, and the carriage on greenscreen on a parking lot, which had been carefully painted to match the paving in the Piazza. Since we didnt have any background plate at all, we fabricated them from still photographs of the location. Those were sometimes heavily retouched so that the angle and the lighting matched the foreground perfectly. We then populated the Piazza with rows of greenscreen extras. A few production shots unexpectedly needed more people in the crowd who didnt match our greenscreen people. In this case, better than setting up a new live-action shoot, we chose to rotoscope extras from other takes and integrate them into these shots.
For Dutton, Casanova started off as a pretty straightforward project, but the movie eventually turned out to be one of the companys most difficult assignments ever. There were so many problems that we had to solve. Some solutions we found early on by Bill carefully preplanning everything, but many shots had to be designed at Illusion Arts in post-production, just because they were never meant to be effects shots in the first place. It was tough, but it was a lot of fun too
Alain Bielik is the founder and editor of renowned effects magazine S.F.X, published in France since 1991. He also contributes to various French publications and occasionally to Cinefex. He recently organized a major special effects exhibition at the Musée International de la Miniature in Lyon, France.