The American Society of Cinematographers

Loyalty • Progress • Artistry
Return to Table of Contents
Return to Table of Contents December 2015 Return to Table of Contents
ASC Close-Up
The Good Dinosaur

A Q&A with Sharon Calahan, ASC, about the cinematographer's role in digital animation.

Photos courtesy of Pixar Animation Studios.

In the alt-fiction world of Pixar’s The Good Dinosaur, the event that made dinosaurs extinct never happened: the fateful asteroid never hit the Earth. Consequently, talking dinosaurs share the world with other species, including humans. The story follows a cowardly young Apatosaurus, Arlo, who tries to return to his family after he is separated from them by an accident in a raging river. Along the way, he makes new friends and encounters some frightening predators.

Sharon Calahan, ASC, a longtime member of Pixar’s creative team, served as both the visual designer and director of photography-lighting on the film. AC spoke with her recently about her contributions to the project and, more broadly, about the cinematographer’s role in digital animation.

American Cinematographer: Was your role as visual designer a facet of the cinematography or a totally separate position on the project?

Sharon Calahan, ASC: It was separate. The design work starts much earlier in the process. I work closely with the production designer on the look of sets and locations, fleshing out how sets are surfaced, how they’re dressed, what colors will be used, and so forth. [The role] touches on everything that goes into the image, including the visual-effects work and how all of the effects will be integrated into the picture. It also concerns all the physical simulations — how the wind and trees interact, for example. And, of course, I work on the lighting design. I spend a lot of time very early in the process creating concept art and painting lighting keys for the crew, so they all understand where we’re going and have a reference for that work.

Where do you start when you’re building the whole world from scratch? Do you look at real locations?

Calahan: Yes. The director, Pete Sohn, asked where we should set the film. I had spent a lot of time painting in Wyoming, near Jackson, and I thought that environment fit the needs of the story, so I pitched it. We scouted around there, and Pete fell in love with it.

When you scout, are you taking photos or video? Are you actually capturing physical details to turn into computer models?

Calahan: I have a Canon EOS and a digital Leica. We used pictures and video for reference to build the locations [digitally], not to capture actual geometric data. We also went to Yellowstone National Park. Because I’ve spent a fair bit of time in that neck of the woods, I also had a large library of my own photos. We also took some GoPros and went white-water rafting to experience what it would be like for Arlo as he moved down the river. We did a lot of work on the previsualization using this material and a lot of data from the U.S. Geological Survey. Sometimes we used the terrain directly as a guide, and sometimes we’d customize it to our needs.

Where does the script stand at that point in the process?

Calahan: The script was more of a treatment at the time. It was a short schedule from the time we actually got the green light, and we needed to get going on the visuals. By the time the actors were ready to come in and do their parts with Pete, they were given a full package that included representations of their characters and other artwork that helped them get a sense of who they were playing and what the environments would look like.

What happens next?

Calahan:The animators animate the characters using Presto, our proprietary system. They build 3-D models and procedural characteristics for movement. Then the sets department creates all of the sets and backgrounds, working primarily in Maya. That work is then converted into Presto. Then we do a rough blocking of the scene with the camera. Mahyar Abousaeedi, the director of photography-camera, worked with Pete on choosing focal lengths, camera placements and camera moves. Together we discuss depth of field and other particulars. Usually, once they have roughed out a scene in Presto, I block in a lighting pass. I don’t lock myself into anything, but it provides a rough guide for the lighting of the scene. This was especially important on The Good Dinosaur because everything is outdoors, and the lighting indicated the direction of the sun and its placement in the sky.

Once the animation is done or almost done, and we have a blocking pass that establishes what the characters are doing in the frame, we go back in and start refining our final pass. We progress from rough to fine; we start out broad as we’re blocking light to the camera, and then we keep refining the lighting. It's a very iterative process.

Do you use terminology that live-action cinematographers use, like ‘reflectors’ and ‘bounce boards’?

Calahan: Yes. In fact, we have to. Even ‘sunlight’ has to be finely detailed. Say, for instance, that we want the sunlight to have a soft haze to it. By default, our sun is like the sun in outer space, where there are no atmospheric effects to soften it. So we have to mold it, as well as create all the indirect light. I might call for a ‘bounce’ or a ‘cucoloris.’ As tools evolve and we refine our processes, I think our work gets more like live action all the time.

Is all that work happening within Presto?

Calahan: No. The lighting tools in Presto can only give us a rough blocking pass. For The Good Dinosaur we had another proprietary package of software, Lumos, that extracted that information from Presto and allowed us to do the detailed lighting work. For future shows we are evolving to a customized lighting package using Katana.

Were you involved in the development of Lumos?

Calahan: Over the years, yes.

Within Lumos, do your light sources have the same names as real-world instruments?

Calahan: Not really. We have different styles of lights. We have lights that are infinite, so they cast parallel rays, and lights that are local, so they cast radial rays like a lamp would. Then we give them different parameters to color them or shape them or change their falloff; we can even effect a color change over distance. There are many different layers we can put on our lights, and their size and intensity can be infinitely controlled. So, calling something a ‘20K’ wouldn’t really mean anything. However, the functionality is the same in terms of how we might use it. Typically, what we do is design a light, give it a variety of parameters, and then say, ‘This is the sunlight for this set, and it has these 15 parameters.’ We also might set up a lighting rig for a character that has a key, a fill and a bounce light, and essentially attach that to the character so it follows him wherever he goes.

Is the actual process of lighting a scene just you at a computer?

Calahan: Oh, no! I’ve got quite a big team — 37 or 38 lighters, including four leads, and another group of technical support that we call the Lightspeed team.

And everyone is at workstations at same time?

Calahan: Yes, and we are usually working on many scenes at the same time. I’ll do what I call walk-throughs, where people on my team show what they’re working on, I give feedback, they go away and work on it, and then they come back the next day and show the progress. It’s definitely an iterative process; nothing happens in real time. I might be looking at pre-lighting for 10 sets plus shots for another 10 sequences concurrently.

Do you just watch everything on monitors, or is the material projected in a theater?

Calahan: Once we get close to what we think is final footage, we screen what we call ‘digital dailies’ at film resolution in the theater. Up to that point, we work at lower resolutions, viewing on desktop monitors, so the material will render faster. When we take it into the theater and review it, we go shot by shot. If that looks good, we approve it conditionally and move it along. When the sequence is close to being finished, we’ll do a continuity review on the same material to make sure we haven’t missed anything.

In general, is it more challenging to achieve some kinds of shots than others?

Calahan: Yes. The more detail you see in a scene, the bigger the challenge. The lighting department is the funnel into which everything falls. When we get into lighting a set, even if I paid attention to how things were coming along upstream, I might find that the grass is the wrong color under the lighting conditions, or that those five different types of grass don’t react to light the same way, so we have to massage them. Generally, a wide shot is harder to light than a close-up. And a moving-camera shot is more challenging than one where the camera is locked down. The trickiest shots are usually the ones where we are animating the lighting to transition from one look to another.

Did you study cinematography in school?

Calahan: I went to art school and studied illustration, still photography and graphic design. I stumbled into computer animation by accident many years ago, fell in love with it, and decided I wanted to make movies with it. One thing led to another, and here I am!



<< previous || next >>