How visual effects for 'The Jungle Book' and 'Doctor Strange' were made

— -- During movie awards season, a lot of attention is given to the Oscar-nominated actors and directors. But what about the nominees whose job responsibilities aren't quite so obvious to the average moviegoer?

For a new series called "Behind the Lens," ABC News got to know the people who were recognized for work behind the camera.

Adam Valdez and Stephane Ceretti, the visual effects supervisors for "The Jungle Book" and "Doctor Strange," respectively, explained how much work they poured into their films and how they created movie magic.

The best visual effects Oscar dates back to 1963, and back then, only two films were nominated.

As technology has evolved, so too has the award -- and each year since 2009, five films have recognized for their achievements in the field.

This year, two of those movies are Disney's "The Jungle Book" and Marvel's "Doctor Strange."

Though the films couldn't be more different -- "The Jungle Book" focuses on a little boy living among animals in the wild, while "Doctor Strange" is about a physician who uses sorcery to defend the world -- both were created by special effects teams comprised of hundreds of artists who took many months to complete their work.

"People don't realize how much work goes into every single frame that we do and how much thinking goes into every single shot that we do," Ceretti told ABC News.

"It's really hard to do this," Valdez agreed. "It not only takes creativity and technical skill, but a lot of diligence. If something there was slipping slightly I think your eye would catch that and it would kind of break it. As an audience member, then you start thinking about how this was made and while it's nice to talk about with you now, we don't have anybody thinking about it while they watch the film."

He had his work cut out for him. "The Jungle Book" was shot entirely on a sound stage in Los Angeles, and practically every element other than Neel Sethi, the actor who plays Mowgli, was computer-generated. Though Valdez acknowledged that they could have shot on location somewhere, he noted, "Not only are the events that are happening special, but the world we're creating with our director Jon Favreau here at [the film studio] MPC is a special place too."

To help them create the animals, Valdez's team collaborated with puppeteers at the Jim Henson Company, who made puppets that stood in as wolves and panthers on set. They also had specialists working on every aspect of the film, from lighting to cinematography, similarly to how a live-action film would be staffed.

"All of the stuff you're seeing here is made in the computer as three-dimensional geometry," he said. "We start often with the background image of the sky, but you'll see every layer is created. We dressed thousands of plants into the scenery individually. ... We color it, we light it, we add texture and shape to everything."

It's a similar process to the one employed by Ceretti's team at Marvel. Though "Doctor Strange" was at times shot on location, Ceretti and his team of several hundred had to animate everything in advance so that when star Benedict Cumberbatch was ready to shoot the movie, the director knew exactly what to tell him to do. However, changes were made up until the last minute, he said.

"The way Marvel films are done, we do a first pass of the film and then we look at it and we see what works," he said. "There's always new ideas. It's a very collaborative process. We have tons of people adding fancy cool ideas and we're like, 'Why haven't we thought about that?!' and we start seeing if we can put it into the film. If it makes sense for the story, we will pick it up. ... We never stop trying to push the film to be better."

There were stylistic concerns for "Doctor Strange" too. Ceretti said that many of the effects were we based on the art of M.C. Escher, and because the original cartoon was made in the 1960s, the team wanted to give the film a psychedelic feel.

"We have some very grounded real world things ... and then we go into these dimensions and we went crazy about colors ... [and] optical illusions," he said. "We wanted to pay homage to what [artist] Steve Ditko had done in these years so as soon as we go into the crazy rooms. ... We went really strong on colors and playing with the black light effect. It was about creating something that was very different."

Given the amount of work that went into their projects, both VFX supervisors were thrilled to earn Oscar nominations. Both were also quick to point out, however, that they were sharing it with their teams.

"Everybody has worked really hard, so I feel blessed that I have the opportunity to represent their work," Ceretti said. "It's super exciting."

"It's nice to recognize the fact that filmmakers are trying so hard to make amazing experiences for audiences and that that trickles down to, again, hundreds of artisans who are really crafting this stuff," added Valdez. "It's all great. To have a movie that is well done and people go to see it and they like it and then to have all these MPC artists be recognized ... it's just amazing. It feels wonderful."

To learn more about how Valdez and Ceretti created the visual effects in "The Jungle Book" and "Doctor Strange," watch the videos above.

Disney is the parent company of ABC News and Marvel.