Robert Zemeckis and his cinematographer Dean Cundey went into a meeting with Disney where they were told everything they could not do to make “Who Framed Roger Rabbit.” Walt Disney himself got his start making live-action and animated hybrids as far back as the 1920s. It was fused in the DNA of the company. Execs there knew best.

Don’t move the camera, don’t shoot close-ups, don’t get fancy with lighting. Basically don’t do anything that would take too much work for the animators.

That didn’t fly for Zemeckis.

“When Bob and I left the meeting where they had said six or eight things that we should or couldn’t do, Bob and I said, ‘Well, those are the rules we’re going to break. How are we going to do it?'” Cundey recalled in an interview with TheWrap to commemorate the film’s 30th anniversary.

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Based on Gary K. Wolf’s satirical noir novel, “Who Framed Roger Rabbit” blended live-action and animation and introduced technology that set a benchmark for what movies could look like. It fed directly into computer-generated spectacles like “Jurassic Park” and proved that using a bigger budget on special effects could reap gigantic rewards at the box office.

And yet despite being highly influential, “Who Framed Roger Rabbit” does not have any contemporaries that use the same techniques it did in 1988. The film doesn’t look old fashioned or out of date, but it certainly doesn’t look like any movie made in 2018 either. Now, 30 years after its release, “Roger Rabbit” feels completely of its own time and is truly one of a kind.

“[Zemeckis] would say, ‘Well anybody could do that. What are we going to do?’ He was always interested in thinking outside the curve and doing something new,” Cundey said. “It was a refreshing challenge for me knowing I would be supported with weird things I would think up. Bob was not afraid or intimidated by the technology. He just wanted to take people somewhere they hadn’t gone before. So with that in mind we just set out on the journey.”

Historically, movies like “Mary Poppins” and “Pete’s Dragon,” which also combined cartoons and humans in the same frame, have had the problem of characters that looked pasted onto the screen. Eye lines rarely matched, so actors looked through the cartoons rather than at them. And even if you had Dick Van Dyke dancing with penguins, they never seemed to truly occupy the same space.

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“Who Framed Roger Rabbit” changed that. Using traditional pencil drawn animation that gave the illusion of depth and new technology that allowed drawings to be printed directly onto a frame of film, the cartoons of “Roger Rabbit” not only convincingly shared the screen with real humans, they interacted with the real world.

For instance, when Roger is hiding out from the cops, he casts a real shadow on the wall that’s the same size as the humans. When the weasels raid Eddie Valiant’s apartment, they wave real guns rather than drawn ones, all of which had to be manipulated on strings and with mechanical props. And when Jessica Rabbit takes the stage and grabs Eddie by the lapel, the backlit spotlight makes her glow like a sultry 1940s starlet.

Disney and other animation veterans explained to the filmmakers that by moving the camera or tinkering with cartoons moving in and out of light, it’d be twice the work and too much of a strain on the animators, Cundey explained. Previously, animators had gotten away with drawing on just 12 frames per second rather than the standard 24 as a way of reducing the workload. So they turned to Canadian Richard Williams, who had broken all the rules on a series of commercials he had already done for Disney. When he told Zemeckis that everyone else was just being lazy, they knew he was up to the task.

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“Bob said, ‘I want to shoot it like a modern movie,'” Williams recalled in an interview with TheWrap. “I said go ahead. [He said,] ‘Isn’t that a lot of work?’ I said, ‘You betcha!’ ‘We have to fit all the drawings into 8/24ths of the frame, and you have to turn everything.’ ‘That’s our job! That’s what we do.”

Before production began, Cundey and Williams worked with Zemeckis to shoot a brief teaser that would show off to Disney what they could do. They called it an “obstacle course” that showed Roger Rabbit stumbling down a flight of stairs, moving in and out of light, talking with Eddie and even knocking over a garbage can. It was a sample of everything they wanted to accomplish in the feature film.

Williams’s concern however was the “pasted on” look of live-action/animation hybrids. But over at Industrial Light and Magic, visual effects pioneer Ken Ralston had developed an optical printing technique that Williams called the “missing link.”

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“When we would send the film to ILM, they would composite it and we would see what they did, everybody got turned on,” Williams said. “The damn thing’s working!”

Cundey said he and his crew had already taken the pains while shooting to meticulously plan and choreograph shots as though Roger and the other toons were actors on set. The cinematographer told TheWrap they used life-size, rubber puppets as props so that Bob Hoskins and the other actors could have a reference to know where to look. And Cundey would then instruct his camera operators to move as though they were reacting to a real world action happening in front of them, even going as far as to deliberately place chairs and obstacles in their way.

Doing the bare minimum in service of the story wasn’t enough for Zemeckis. In one early scene, a long tracking shot follows Eddie as he walks through a studio backlot full of auditioning cartoons, many of which have no dialogue and are there purely to populate the world. In another scene, Roger bumps a lamp swinging in a hidden back room, and the constantly moving light provided an added challenge for the animators.

Cundey said that every interaction between the cartoons and the real world, every shadow and every interaction was done to make the audience believe the fantasy.

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“There was no bare minimum. Everybody was trying their very best,” Williams added. “We all knew it was going to be a hit. The whole staff. Everybody knew it. You could just smell it.”

Williams furthered this illusion by coming up with the idea to make the cartoon characters “2.5-dimensional.” Rather than fully 3D, they’re hand drawn to look like classic, two-dimensional cartoons of the ’30s and ’40s, then given shadows, layers and texture that makes them look as though they have depth. Williams described it as “Old stuff inserted into new stuff, using new techniques,” and it’s the reason why “Roger Rabbit” still stands apart from the CGI movies of today.

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“You exaggerate and you invent. It’s the invention, especially when you’re looking at those old cartoons, they’re doing crazy stuff. That’s not realism,” Williams said. “By doing it 2.5 dimensional, it looks like the old stuff, and the old stuff is inventive. So drawn animation, by it’s own nature, you have to invent.”

“They developed a completely new technique in order to create this illusion of shape. So it was that kind of dedication,” Cundey said. “They could’ve easily said they would just composite these flat characters, but creating this illusion of shape was something they did, and it was essential to the end result. So when I saw the final film, I was as surprised as the audience.”

“Roger Rabbit” went on to gross $329 million worldwide and win three Oscars, including for its visual effects. So inevitably, there’s always talk of the sequel. But if one was done today, the production would likely utilize motion capture technology and computer generated animation, and the charm wouldn’t be the same.

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“There’s very little pencil animated stuff,” Cundey said. “The easy and I think sometimes lazy way for animators is motion capture. It’s the easier thing to do for ‘Planet of the Apes’ and so forth. It certainly looks more real, but I’m not sure that motion capture would be what we would expect out of a ‘Roger Rabbit’ sequel.”

Rather, what made “Roger Rabbit” special was the dedication that went into every detail, the degree to which the filmmakers went above and beyond to make it work.

“Our job is always to create illusion and to get an audience to believe and then want to come and see and tell their friends its awesome. How to do that stuff is always left to the few pioneers who either are determined or able to understand it and take the techniques to the next step,” Cundey said. “Sometimes it’s driven by what’s easier. Let’s lop off the camera in a big wide shot and the animators will use it just like they would use one of their painted backgrounds. It’ll just be a frame of a camera. It’s too hard to track the camera movement. Well, someone else says, it’s hard, but it’s worth it.”