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It’s the season for superheros and the supernatural, as the new crop of summer features comes to a multiplex near you.Visual effects studios, whose modelers, animators and compositors have been toiling on these films for some time, join eager audiences nationwide in seeing how their efforts play on the big screen. Tippett Studio (www.tippett.com) in Berkeley, CA, created 101 shots for The Smurfs.While Sony Pictures Imageworks handled the bulk of the film’s animation, including the Smurfs themselves,Tippett focused on several key sequences, including the arrival of Gargamel (played by Hank Azaria), the Azrael and Smurfette chase sequence, and the hairball scene.The studio also created 10 end-stills for the final credits, which were produced at 4K resolution and rendered by SPI. Although four real, look-alike cats were on set to perform as much as any trained cat can,Tip- pett stepped in with the CG Azrael when “we had to amp up the cat to hold its own against Hank,” says co-VFX supervisor Scott Liedtka (Tip- pett’s Blair Clark was VFX supervisor). “The real cats all had different strengths — one could hit the mark and run, one wouldn’t freak out on the street, one was a good jumper and one could sit still for close-ups. But we knew the cats just wouldn’t work for some shots, especially where cat’s lip shapes and expressions,” Liedtka explains. Tippett also deployed its proprietary Furator fur system, which had been completely rewritten for Cats and Dogs. “We had 14 different characters to build for that film,so we retooled the system to make it easier for fur groom- ing and color,” he notes. The Smurfs is an example of the increasing use of image-based lighting, he reports.“On the set we captured information about the high dynamic spher- ical range that we could use to light the CG. Led by CG supervisor Charles Rose, one of our graphics programmers, Andrew Gardner, developed cus- tom tools to process the spheres and make them more useful, and di- rectable, in the lighting pipeline set up by lead TD Larry Weiss.” L-R: Tippett’s William Groebe, Scott Liedtka and Andy Hass at work on the photoreal cat, Azrael. Azrael needed to communicate an emotion: disgust, anger, ferocity, laughter. We completed a little over 100 shots that were either digital face replace- ments or a completely CG cat.” Tippett has crafted CG cats before, he notes.The main difficulty with Azrael was making it look like the cat actor on screen.“It’s easier to create a CG animal when it has no live counterpart,” Liedtka points out.“A lot of dif- ferent little things can say,‘that’s not the same animal.’You have to build an an- imal that will match well in every way: anatomy, dimensions, skeleton, move- ment, color, fur, eyes, teeth, claws. Our art director Nate Fredenburg super- vised extensive reference data collection for our modeling.We had lots of photos from multiple cameras that captured the cat actors from different an- gles at the same time.” It was Tippett’s goal to be “confident that when we put our CG cat in the shot we’d have an asset that was going to work so we wouldn’t have to go back and change the model.” Tippett used Autodesk’s Mudbox for sculpting the CG cats and Maya as the main animation tool for rigging the felines.“We have a well developed team of animators and riggers who are experts at selling realistic animals of all kinds,” says Liedtka.“Where Azrael is not doing some cartoony ac- tion, he has to be really believable, like when he’s throwing up a hairball — the way that unfolds looks really convincing.” Lead FX artist Joseph Hamdorf used Side Effects’ Houdini for fluid simulations, including the goo-covered hairball. Azrael does not talk, nevertheless Tippett built a full face system, using the studio’s proprietary Face Rig, based on speaking should the need for that capability arise. Even without speech, the cat’s varied expres- sions proved to be “a ton of work — it took a lot of modeling and wiring up to give the animators control of the About a dozen of Tippett’s Azrael shots involve the CG cat interacting with a Smurf; it shared these sequences with lead VFX house Sony Pictures Imageworks. Shots such as Smurfette jumping on Azrael’s back and riding him like a bucking bronco were especially complex. “With fur, you couldn’t be sure exactly where they were touching each other,” Liedtka recalls.“It required a lot of complicated back and forth with Sony; at each stage we were updating each other.They gave us a model of Smurfette and a simple generic rig, which was very useful, and at the end we were trading renders, doing test composites, fur interaction and shadowing.” Compositing supervisor Colin Epstein oversaw a transition from Apple’s Shake to The Foundry’s Nuke for compositing. The Smurfs is being released in stereo 3D but Tippett was not required to deliver stereo pairs of images. Instead, the studio gave break outs to the stereo vendor to enable them to craft extra dimensional layers. For example, “we delivered fine lines, like the whiskers around the cat’s nose, separately so the stereo vendor could handle them with more precision rather than ex- tracting them from the image they were baked into,” says Liedtka. “We also made mattes and Z-depth images for the vendor.” Tippett had worked with director Raja Gosnell on Beverly Hills Chichuahua, and he trusted the studio to explore and “find the funny” in some shots.“He’d kick off the sequence and we’d play around with it, finding the unexpected and throwing it in,” says Liedtka.“Our animation supervisor, William Groebe, is very good at getting a joke, and Raja was always encour- aging him to come up with something funny on his own.” GREEN LANTERN Sony Pictures Imageworks (www.imageworks.com) in Culver City,CA, has been busy. In addition to their work on The Smurfs, they were also the pri- mary VFX house for Green Lantern, finishing about 1,000 shots for the feature www.postmagazine.com July 2011 • Post 17 . The studio provided 101 shots, including The Smurfs THE SMURFS