Working on Rome environments was CIS Vancouver. Led by VFX Supervisor Mark Breakspear, the team created three CG church environments: Santa Maria della Vittoria, Santa Maria del Popolo and St Peter's Basilica. All three churches were off the shooting grid, so visual effects were the only way they could appear in the film.
The approach was to recreate them digitally, stitching together thousands of digital photographs taken at the real locations, and projecting them onto accurate computer models of the buildings. "We used three Canon EOS 1DS MK2 cameras, with gave fantastic quality in the low light levels of the churches" Breakspear says. "We were not able to get HDR in the truest sense, but we managed to get around that by also shooting with a stills film camera. We used Kodak 5218, which was the same film stock from the main unit shoot. By taking image on film, we were able to make use of the wider range from those images for windows, highlights and areas where we wanted to add detail into the shadow areas. We scanned our film images at 5040 × 3684 @ 240 dpi, while our digital images were captured at 4064 x 2074 @ 72 dpi."
For Santa Maria della Vittoria and Santa Maria del Popolo, the art department built one set that could work for both churches, with a little redress. For St. Peter's Basilica, the actors were shot on an entirely greenscreen set, with only the floor and a partial column to orient the vfx team. "We ended up replacing the column and the floor, but don't tell anyone," Breakspear chuckles.
"For Popolo, there were lots of issues with the practical set not lining up with the real location photography, due to creative license being heavily used in its construction. In the end, we were able to bring both locations together by duplicating areas where needed, and hiding other areas that no longer existed in the practical set. Santa Maria del Popolo was the only church we built using LightWave, everything else was built in Maya. When we worked on The Da Vinci Code, we did all our shots in LightWave, as at the time, our pipeline was more centered around this package for this type of work. Four years later, our pipeline has moved toward Maya, and although we still love what LightWave can do, it made sense to split the builds across both packages. All the churches created in Maya were rendered in mental ray. Each frame was generally broken out into 25-40 specific layers, giving the compositor great control on adjusting the look we wanted."
For Santa Maria della Vittoria, Bickerton shot a miniature of the ceiling and the resulting images were digitally projected onto a CG roof that could be placed in any of the shots. Fire, embers, heat haze and smoke enhancements were also added to the practical fire. All of the compositing was done in Shake.
For St Peter's Basilica, the task was far greater, for CIS had to create just about the entire environment, other than the actor. "Normally, you would try to avoid this, as that much CG real estate is typically very hard to pull off convincingly," Breakspears observes. "Our CG Supervisor, Karen Ansel felt that we could master all the nuances required to fool the eye, and together with 2D Supervisor, Martyn Culpitt, worked out all the required layers and approaches needed to pull it off. The end result is pretty amazing!"
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