Joe Letteri started out at George Lucas's firm, Industrial Light and Magic, and was one of the people responsible for the dinosaurs of Jurassic Park.
He joined Weta for the Lord of the Rings trilogy, just in time for another game-changer, the creation of the first truly digital character, Gollum.
Letteri’s currently working on not one but four sequels to James Cameron's blockbuster Avatar and he told Simon Morris that no matter how sophisticated digital effects become, they must always be in service of the story.
“If the story's not there, the work doesn't matter,” Letteri says.
Jurassic Park was the realisation of a boyhood dream writ large, he says.
“I remember sitting in school in third grade, drawing dinosaurs and to be able to create those brachiosaurus and those T Rex was just fantastic.
“But we had a long way to go to be able to do it in any kind of a sense where it was really a kind of a common toolkit for directors to use.”
Because of the difficulty in rendering dinosaurs digitally back in 1993, director Steven Spielberg had to use the footage they created sparingly, Letteri says.
“Jurassic Park only had about 65 shots of our digital dinosaurs. You know, we had Stan Winston's animatronic dinosaurs that were mixed in, but there was less than 10 minutes’ worth of our work in there.
“But Steven used it very judiciously, I think a lesson he had learned from Jaws about how to get the most impact from it. It took us a year to do, now we routinely do hundreds of thousands of shots for a film.”
When James Cameron sent him the script for Avatar, Letteri says he jumped at the chance to create a world from scratch.
“Not only was it a fantastic story, but it was a fantastic world. It allowed us to really go to a different planet and create the whole thing. So, we embarked on this big research and development campaign to understand how do make a planet and everything that goes in it.”
Despite the world being entirely imagined, it nevertheless had to be grounded in reality, he says.
“You always start with reality, always. And then you replace it or enhance it bit by bit to make it go in the direction that you want. So, with a film like Lion King, the whole point was to make it photo real you know, in real nature. So yeah, you get a lot of photograph textures of leaves and bark and kind of put that all together.
"On Avatar we pushed that a little bit farther. We did all that because there's a certain commonality to nature that we thought would always be there, leaves will always be green because you need sunlight and chlorophyll, but we pushed that by adding these exotic plants that only could grow on Pandora, with really rich colours and different unique designs.”
Creating an imagined world like Pandora in the Avatar films must still ring true, he says.
“If you're starting with a blank slate, it's easy to get off track. Now you ask yourself, is this thing too bright? Is that shadow the right colour? Because if it doesn't all come together, you're out of the movie. And you may not know why. But things like nature, things like facial expressions. As humans, we experience that every day.
“So, we may not know if it's right or wrong, but you know when it's wrong. And that's really a in a way a harder balance to maintain.”
Letteri says he relished the chance to make Gollum in Lord of the Rings jump from the screen.
“The opportunity to work on Gollum here on Lord of the Rings, for me was just outstanding. I just jumped on that because creating a character like that, that was so central to the story, you learn so much, but it helps to bring the story alive. He was a great character in the book and I wanted to see what we could do with him on screen.
“And that's something that we've carried on with ever since with King Kong, with Avatar, with the Planet of the Apes films. That's just been our specialty, is to work on characters because they are so much at the heart of the film.”