For use with Chapter 17
Reflection and Refraction
The Devil Is in the Details
Posted March 16th, 2000
is not perfect. In fact, we are so used to seeing imperfections
in everything we see that if something looks too perfect,
it just doesn't look real. Visual effects artists in Hollywood
are constantly working to make their effects look as real
short 10 years ago, when most special effects were achieved
with models, imperfections naturally occurred because the
models were real. Today, many films use computers to generate
virtual "models," and visual effects artists constantly struggle
to add the imperfections to the "perfect" computer images.
most noticeable examples of computer generated "perfection"
occur in the 1995 film Toy Story. This was the first
full-length feature completely animated with computers. The
images in Toy Story appear so smooth and perfect that
it is obvious they are computer generated.
Disney and Pixar produced the blockbuster's sequel, Toy
Story 2, they added some imperfections in various places
- scuffs, dirt marks, and corrosion. The problem is that this
process is extremely time consuming and expensive.
reason we see these imperfections is a result of the interaction
of light reflecting off and refracting through an object's
surface. Two techniques, known as "ray tracing" and "radiosity,"
allow artists to play with the lighting of the virtual model
to increase realism. While these techniques are becoming increasingly
realistic, they still don't produce total realism.
programmers are developing specialized computer software that
will allow artists to "paint" pre-designed imperfections onto
computer models. Artists will soon be able to recreate various
textures and imperfections, from organic images like skin
and fur to solid features like crumbling stones and corrosion.
new techniques are giving virtual model makers a new way to
produce realistic images. This technology is not only used
by Hollywood for special effects blockbusters, however. Corporations,
such as Boeing, is beginning to use such software to make
their training videos all the more realistic.
Watch several movies that contain computer-generated visual effects. Then write a an entry in your science journal explaining whether these effects looked realistic
or not. Be sure to explain how they looked unrealistic, if you do not feel they were.