The Artistic Coordinator
for The Iron Giant
Scott
F. Johnston joined Walt Disney Feature Animation in 1989 during the production
of The Little Mermaid. He continued his work with Disney on other
films, including The Prince and the Pauper (1990), The Rescuers
Down Under (1990), Aladdin (1992), and was the principle designer
of the ballroom sequence in Beauty and the Beast (1991). He also
did work on The Lion King (1994), where he oversaw the development
and producton of all the 3D computer-generated effects, including the
climatic wildebeest stampede that kills young Simba's father, Mufasa.
In 1997 Johnston founded his own studio, Fleeting Image Animation, Inc.
to develop and produce animation, integrating traditional and computer
generated techniques.
"My
involvement with The Iron Giant started in early 1997. Max Howard, then
President of Warner Bros. Feature Animation, and Producer Allison Abbate
were assembling the team for the show and thought I might be able to help
with the challenge of bringing the director's vision to the screen." -
Scott Johnston
Animation
Artist: What were your job duties as the Artistic Coordinator for
The Iron Giant?
Scott
Johnston: Director Brad Bird and Art Director Alan Bodner would say
what they wanted, and I would work with the artistic staff and production
management to figure out how to accomplish it. As the production pragmatist,
I worked with management to weigh creative possibilities against resource
limitations (budget, time... the usual suspects) and then suggest alternate
ways of achieving as much of what we wanted as possible. I often had to
translate semi-abstract ideas into a coherent sequence of steps for the
crew. I'd take care of the details, freeing Brad to focus on the performances.I
tried to keep "the big picture" in mind. Artists often work on very specific
pieces of the puzzle; explaining the broader context of a problem would
often help solve it.
Animation
Artist: What elements of The Iron Giant contained Computer Graphics
Imagery? Also, what program did you use for the CGI?
Scott
Johnston: The Giant and an assortment of animating props--tanks, planes,
trucks, and bikes--were done in CGI. In addition, artists created and
modified artwork digitally for a wide array of effects. Allen Foster and
his crew did an exceptional job of integrating the traditional and digital
effects work. The majority of the CG work was done with Alias|Wavefront's
Maya software package, with many in-house enhancements. The CG levels
were rendered with a modified version of Pixar's RenderMan and transferred
into Cambridge Animation's Animo alongside the scanned pencil animation
and painted BG's. We also used Alias' older PowerAnimator, Avid's Elastic
Reality, Adobe's Photoshop plus a smattering of other programs here and
there.
Animation
Artist: You did a lot of CGI work for Disney's The Lion King. How
do the two films (The Lion King and The Iron Giant) differ in the area
of CGI and what aspects of your experience with The Lion King helped in
your work with The Iron Giant?
Scott
Johnston: CGI was used throughout The Lion King, but the focus of
the CG work involved the wildebeest stampede, which only takes about two
and a half minutes of screen time. While the behavior of the animals in
the stampede needed to be believable, the range of acting and emotions
never approached the complexity of the Giant. The Giant appears in much
more of the film, and the animators needed to make him act with much more
subtlety. The appearance of the wildebeests had to blend seamlessly with
the environment and traditional characters so the emotion of the sequence
would work without a jarring alien presence. The Giant IS an alien in
Rockwell. He needed to be a believable character, but the villain decries
him as an outsider — something that doesn't belong in the human world.
He's a fifty foot-high metal character. He can't help being "different."
Animation
Artist: Please describe for us a typical day in the life of Scott
Johnston as it relates to your work with The Iron Giant.
Scott
Johnston: My schedule changed dramatically during production. Early
on, we spent a lot of time planning the design of the character, building
tools that we would need, creating workbooks for the sequences and trying
to ascertain what we could and couldn't do. Later, a lot of time was spent
adapting to the changes that inevitably occur as a movie starts coming
together. The crew worked hard to give Brad what he wanted--and then some,
but as with any project of this scale, the creators' original intentions
can get lost in pages of notes and changes. I often had to help clarify
these situations. If something was completely unknown, I'd ask Brad, or
make something up—and apologize later if it was wrong. Solving problems
often just amounted to understanding them and bringing the right people
together: knowing who has the answer can be more useful than knowing the
answer. Some days I acted more like a therapist. Artists usually know
how to solve the problems that come up in the course of their work, but
they may need to bounce the idea around or get someone to help them organize
their thoughts. We also had to deal with the whims of technology and had
a crew of engineers continuously improving an overburdened system.
Animation
Artist: How did you successfully bring together the classic animation
look with CGI in The Iron Giant so that it had the right look?
Scott
Johnston: By working with a great team of people. There are four principle
areas that need to be addressed to integrate CG effectively into traditional
animation:
1. DESIGN
The scale and shape of the characters and props had to be in the same
style as the drawn elements in the film. Mark Whiting and Steve Markowski
did the majority of the design work on the Giant, with additional comments
and suggestions from Joe Johnston. Turning those sketches into a working
3D model required patience and the ability to adapt the design to make
it animatable. Hiroki Itokazu not only built all the different versions
of the Giant, but also all the tanks, trucks, cars and other 3D objects
and props in the film. Most films have a staff of people building models.
This guy is amazing!
2. CAMERA
WORK AND STAGING
Most CG is shot through an "ideal" camera, which is like a live action
lens. As the camera moves, everything continually adjusts in perspective.
In traditional animation, multiplane moves can create a great illusion
of depth, but the perspective on individual background elements doesn't
change while the animation camera is moving. The vanishing points are
fixed on the layouts, and the artists often break the rules of perspective
to accommodate the staging. For The Iron Giant, CG animation was shot
with cameras that mimicked the animation cameras used in the rest of the
film. A moving 3D camera quickly reveals the CG nature of a shot, so we
used it sparingly and only for conscious dramatic effect. Tad Gielow was
the CGI supervisor for the film. His crew of Technical Director's (TD's)
included both developers, who wrote the underlying code, and designers,
who orchestrated the scenes, worked with the animators, and pushed the
tools to their limits. In addition to managing the group, Tad added tools
to Maya to imitate a traditional animation camera stand, allowing motion
data to be shared between Maya and Animo.
3. ANIMATION
ACTING AND TIMING
CG is usually shot on ones because it is very easy for a machine to inbetween
everything. Traditional, drawn animation is shot on ones and twos, because
a movement on twos evokes a different feeling that may be more appropriate
for some actions. We used both ones and twos on the Giant. The scale of
the Giant caused special problems: a "small" motion for him often spanned
large areas of the screen, and resulted in too much strobing when it was
shot on twos. Senior developer Mike Meckler engineered the infrastructure
for writing extensions to the software packages we used and developed
the controls within Maya that made Hiroki's models work for the animators.
Senior designer Teddy Yang gave valuable feedback to the developers, and
resolved issues and solved problems for the animators and designers.
4.
RENDERING AND LIGHTING Getting CG to match the drawn, scanned, inked and
painted style of the traditional characters and effects is a difficult
process. We simplified the color design of the character, using basic
areas of light and dark and made minimal use of tones to add "shading."
This technique is often used to give a character depth, and ours already
had plenty. The Giant's color palette was chosen to give us the most flexibility
in integrating him into the film. His dominant color is a neutral gray,
which has a tendency to reflect the colors in his surroundings. Outdoors
at night, his tone cools to be closer to the sky. Inside the barn, he
warms to the incandescent amber of the wood and hay. His color constantly
shifts with his mood and the environment. A lot of work went into developing
the rendering pipeline used for the Giant. Andy King started things off
by getting the scenes out of Maya and into RenderMan. Brian Gardner built
the shader and back-end of RenderMan to create the ink and paint images,
which included detecting the inking lines and rendering them with subtle
imperfections to match the scanned pencil lines from our traditional artists.
The most novel aspect of the Giant's rendering was that the artwork was
delivered to the Color Model department in the same fashion as the drawn
elements. Rather than rerender each scene as the color palettes changed,
Aaron Thompson and Babak Forutanpour wrote a tool to convert the rendered
artwork directly into the format used by Animo, which allows color palette
changes after artwork has been inked and painted. Brett Achorn and Rhonda
Hicks made these tools work for all the CG elements in the film. The Giant
was color-styled uniquely in each scene and balanced with all the other
elements.
Animation
Artist: How difficult was it to animate expressions on the Iron Giant
without losing the Giant's appearance of being an all-metal robot?
Scott
Johnston: One of the reasons the Giant was animated in CG was to prevent
him from having the malleable look of a traditionally animated character.
A series of illustrations by Mark Whiting proved that streamlined shapes
could be used in a variety of positions to express the necessary range
of emotions. Traditional animators often use broadly caricatured eyebrows
to indicate facial expressions. We knew this wouldn't work on our Giant
because eyebrows would look like large refrigerator magnets sliding around
on his face. We wanted the logic of the Giant's design to be as evident
as possible—Why would anyone build a giant with eyebrows—other than for
expressive reasons? Instead we concentrated on the varied illumination
within the eyes and flexibility in the eyelids. The animators could control
where the giant looked, and the dilation of an 'iris' and 'pupil'. Because
of his height, we spend a lot of time looking up at the Giant. Not only
did the expressions have to work without making him seem too elastic,
they had to work from some odd camera angles.
Animation
Artist: What was your biggest challenge with The Iron Giant and how
did you solve that challenge?
Scott
Johnston: The scale of the elements in this movie was a constant challenge.
The Giant's very, very tall, and we shot the movie in Cinemascope, so
the screen is very, very wide. This makes his status as an outsider immediately
apparent: he literally doesn't fit in the world. These scale constraints
made it difficult to establish compositions that conveyed story points
effectively and gave the animators freedom to act. Establishing the relationship
between the CG stage for the Giant and the perspective on the layouts
could be awkward, and often required animator 'cheats' that look okay
on screen, but aren't literally possible. Traditional animators do this
all the time. Because the Giant is so large, a close-up of him is invariably
a long shot of anyone else in the scene. These scale issues also complicated
the layout and background processes.
Animation Artist
magazine is very grateful for the time Tony Fucile took to share his excellent
insight with Animation Artist readers.
All images on this
page are ©copyright 1999 by Warner Bros. and used with permission
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