American Cinematographer - September 1992 - 32

Down and

encircles it is a five-kilometer bound¬

Dirty

Much computer art of the
past carried with it a surreal cleanli¬

"We

supply equipment that

entertains the world"

You can move lights or objects
anywhere within that space."

ary.

since computers tend to render
objects with a kind of sterile perfec¬

ness,

tion. To counter this

"Mathematical

Cinematographer"

look, Founda¬

The individual elements are

tion

Imaging uses Toaster techniques
ships, placing
fuel stains, bums and carbon scoring
on the
engine exteriors in an effort to

to dent the surfaces of

create the

well-used,

characterized

worn

look that

spacecraft in Star Wars

and Alien. Textural subtleties like

dirty mattes can be overlaid on the
surface just as one would dirty up a
miniature with

ond-

an

air brush. A

sec¬

third-image matte can be
placed on top of this to simulate
specularity.
Once the drafting and tex¬
tural process is completed, the data
is stored on DAT tape for safekeep¬
ing. Now the programmer can posi¬
tion the object anywhere on the
monitor. The scale or perspective of
the object can be adjusted, thereby
controlling the distance or depth at
which the object is viewed. Thornton
prefers using a normal television
or

screen

when he works, rather than a

high-resolution monitor, to see how
the finished product will look at
home. His normal office system in¬
cludes a $4000 Toaster with CPU and
screen. He needs no time-base cor¬
rector since he's not going to video at
this stage.
When the user is fairly con¬
fident that there are no holes in the

image and the ship's typography is
perfect, he or she is ready to proceed
to the next step in the drafting opera¬
tion. Backgrounds are created as
separate objects. For starfields,
single-point polygons or white dots
are
generated randomly inside a

Equipment rental, sales
and service for the film

and television

Lighting

-

industry

Grip

-

HMIs

2, 3 & 5 Ton Grip Trucks

Expendables - Generators

sphere. This sphere encompasses the
entire illusionary stage encircling the
computer model of Babylon 5 and
the planet around which it is orbit¬
ing. A nebula can be a simple cloud
with a painted texture mapped onto
it. Even an actual constellation sky
map could be inserted for an accurate
representational view of the night
sky as seen from Earth, if required.
"Essentially, what you have
is a fully equipped production studio
inside your monitor," offers Bryant.
"All the facilities

are

inside

as

well.

Our set for

Concept Lighting/Grip
11274 Goss Street

Sun

half

a

kilometer. The universe that

Valley, CA 91352

(818) 767-1122
30

Babylon 5, electronically
speaking, is five kilometers across.
The space station has been scaled at

Fax (818) 768-9900

September 1992

loaded into tht.

layout area, akin to
bringing miniatures and lights onto
a sound
stage. In effect, the program¬
becomes

mer

a

"mathematical cin¬

ematographer,"
using
the
computer's abstract version of paintby-numbers.
At which angle will the
lights be placed? To answer this
question, the texture of each object
must be

considered,

as

well

as

the

position of the sun in relation to the
planet and ship. Metallic surfaces
reflect light onto other objects and are
composed of highlights. Matte sur¬
faces, on the other hand, scatter light,
retaining a gradated, fairly uniform
cast. Once the reflective characteris¬

tic of each surface is known,

then the
type of light source which is hitting
it must be decided upon.

Using the Video Toaster,
lights the object with program¬
mable lamps which are exactly the
same as
stage lights. Available light
types include distant (directional)
sources like the sun with highly par¬
allel light beams, point sources with
variable intensity falloff, spotlights
with adjustable cone angles and soft
edges, or multiple colored light
sources with gels and animated flick¬
ering intensities.
"Once the cone angle is de¬
fined, you can position your camera
in the middle of the light [as if it were
invisible] to see exactly where the
light is looking if you want to illumi¬
nate a particular spot and track it,"
says Thornton. "For harsh sunlight in
space, you would use a distant light
source
creating parallel beams across
one

the entire universe inside the ma¬
chine. No matter how much you
move

will

[in space], the angle of light

never

change. As the object

turns, the shadows will change over
it. You could synthesize movement
of the sun [for a speedy time-lapse

effect] by changing the angle to cre¬
ate

an

elongation of shadows, but

that's unrealistic."
At this stage one must ren¬
der certain frames to see how the fin¬
ished product will look. Lights are
moved and ambient levels are ad¬

justed. This is similar to wedging

a
American Cinematographer - September 1992

Table of Contents for the Digital Edition of American Cinematographer - September 1992
