Graphics Programs Reference
In-Depth Information
Lighting
Although CG lighting techniques may seem completely different from lighting in real
life, the desired results are quite often the same. The more you understand how real lights
affect your subjects in photography, the better you'll be at CG lighting.
Without lights, you can't capture anything on film. How you light your scene affects
the contrast of the frame as well as the color balance and overall design impact. If the
lights in your scene are too flat or too even, they will weaken your composition and abate
your scene's impact.
As a good way to understand the essentials of lighting, you should take a look at the
three-point system
. This method places a
key
light in front of the scene, which is the pri-
mary illumination and casts shadows into the scene. The key light is typically placed
behind the camera and off to the side to create a highlight on one side of the object for
contrast's sake. The rest of the scene is given a
ill
light. The fill acts to illuminate the rest
of the scene but typically isn't as bright as the key light. The fill also softens harsh shad-
ows from the key light. To pop the subject out from the background, a
back
light is used
to illuminate the subject's silhouette. This is also known as a
rim
light, because it creates
a slight halo or rim around the subject in the scene. It's much fainter than the key or fill
lights.
You'll learn more about Maya lighting techniques in Chapter 10.
Basic Animation Concepts
As mentioned at the beginning of this chapter, animation is the representation of change
over time. This concept is the basis for an amazing art form that has been practiced in
one way or another for quite some time. Although this section can't cover all of them,
here are a few key terms you'll come across numerous times on your journey into CG
animation.
Frames, Keyframes, and In-Betweens
Each drawing of an animation—or, in the case of CG, a single rendered image—is called
a
frame
. The term
frame
also refers to a unit of time in animation whose exact chrono-
logical length depends on how fast the animation will eventually play back (frame rate).
For example, at film rate (24fps), a single frame lasts 1⁄24 of a second. At NTSC video rate
(30fps), that same frame lasts 1⁄30 of a second.
Keyframes
are frames in which the animator creates a pose for a character (or what-
ever is being animated). In CG terms, a keyframe is a frame in which a pose, a position,
or some other such value has been saved in time. Animation is created when an object
travels or changes from one keyframe to another. You'll see firsthand how creating poses
for animation works in Chapter 9 when you create the poses for a simple walking human
figure.
