'Ghostbusters': How the Visual Effects Team Brought Slimer and the Stay Puft Marshmallow Man Back to Life

Ghostbusters Ghosts Still - Publicity - H 2016
Courtesy of Sony Pictures

Ghostbusters Ghosts Still - Publicity - H 2016

While all the pre-release controversy surrounding the new Ghostbusters may have swirled around the casting of four actresses, for the visual effects team working on the new movie creating a new generation of ghosts posed just as much of a challenge.

In the original 1984 Ghostbusters, Ivan Reitman's classic comedy of the supernatural starring Bill Murray, Dan Aykroyd, Harold Ramis and Ernie Hudson, the ghosts were primarily created using puppets and maquettes that were optically composited into the shots — as for the Stay Puft Marshmallow Man, he was a guy in a suit.

That might sound primitive compared to the digital effects available today, but at the time it was considered state-of-the-art. In fact, the film earned an Oscar nomination for its visual effects.

Three decades later, when VFX supervisor Pete Travers of Sony Pictures Imageworks was tasked with bringing Slimer, the Stay Puft Marshmallow Man and a collection of new ghosts to the screen in Paul Feig’s Ghostbusters reboot, the job involved wires, CG, a Slimer redesign and even use of a drone as a stand-in for one of the ghosts.

But even though visual effects have changed dramatically over the years, the production harkened back to the original movie so that the new actors — Melissa McCarthy, Kristen Wiig, Kate McKinnon and Leslie Jones — could interact with "the ghosts" on the set.

“There’s a reverence to the first movie; Paul wanted to make this an entertaining and fun film; he wanted it to be scary, but for comedy to be paramount," says Travers. “Obviously there’s been a lot of advancements in VFX. Paul was a fan of the original Ghostbusters and he was hopeful, as much as possible, to have the ‘real' ghosts on set with the actors. We worked closely with costume and production design, and stunts to make that happen."

The first apparition that the Ghostbusters encounter, Gertrude, who is discovered in a historic home, is a prime example of how several of the "new" ghost characters were created. Feig cast actress Bess Rous as Gertrude, and she played this role on set, supported by wires or a moving platform.

To get the glow, LED lights were sewn into her costume. “This way we had the light reacting to the environment and the actors and the ghost herself. And the Ghostbusters could react to the ghost and not act against a tennis ball," says Travers.

Travers explains that in most of the finished shots, the face and most of the ghost's body belongs to the actress while Gertrude's lower body was hand animated. For shots where the ghost is fully digital, the live-action photography was used as reference by the VFX team that included Deluxe’s Iloura, which created Gertrude, as well as Imageworks, MPC and Zero VFX.

Feig also brought back some of the most popular ghosts from the 1984 film, such as Slimer, who was a puppet in the original. Now he’s fully CG, but Travers reports that they did have a puppet on set, again for lighting and reference. Slimer's look was a sort of hybrid.

“We researched Slimer in the first two movies and even in the cartoon, and we found numerous designs," says Travers. "We went through an iterative process with Paul, showing him different looks, and we ended up with this amalgamation of what people remember.”

The Stay Puft Marshmallow Man was also created digitally this time around, but he appears as a sort of Macy’s Thanksgiving Day Parade balloon. “It’s one of my favorite sequences,” says Travers of the scene. “He had to behave like a balloon. On set, we had interior-lit balloons for motion and lighting reference. It was about 16 ft. in diameter.”

One of the most inventive approaches was used on a ghost that appears at a rock concert, floating about a crowd. The final ghost is digital, based on motion reference provided by a stuntwoman.

But how do you create a ghost for on-set photography that can hover in the air, provide the proper lighting for the photography, and give hundreds of extras an eyeline to watch? The team came up with a clever idea. “We used a drone covered in LEDS,” Travers revealed, adding with a laugh, “It worked great. Drones have been used with cameras in production, but I don’t know if any have been used to mimic a ghost yet.”