Datasheet
MOVIE FILES
Animations can also be output to movie files such as AVI or QuickTime. These usually
large files are self-contained and hold all the images necessary for the animation that they
play back as frames. Like image files, movie files can be compressed to keep their sizes to a
minimum, but they suffer from quality loss as well.
Maya can render directly to an uncompressed AVI movie format, saving you the seem-
ing hassle of having to render out a large sequence of files as TIFFs or such. Although this
might seem like a good idea, you shouldn’t render directly to a movie file. It is best to ren-
der a sequence of files, which can easily be compiled into a movie file later using a pro-
gram such as After Effects, Premiere, or even QuickTime Pro.
The reason is simple: nothing is perfect, and neither is rendering on your computer.
At times, your render will crash or your machine will freeze. In such an event, you need
to start your AVI render from the beginning, whereas with TIFFs you can pick up right
after the last rendered frame. With a sequence, you also have the option of reordering the
frames or easily adjusting a few individual frames’ properties such as hue or saturation
without affecting the entire movie file.
Color
Color is what we perceive as the differences in the frequency of light. The wide range
of colors that we see (the visible spectrum) results when any of three primary colors of
light—red, green, and blue—are “mixed” together. Color can be mixed in two ways,
subtractive and additive. These color definitions are most often displayed in color wheels,
which place primary colors equally spaced around a ring and place the resultant colors
when primaries are mixed in between the appropriate primaries.
Knowing more about color will help you understand how your CG’s color scheme will
work and help you to design your shots with greater authority. (See the reading list at the
end of this chapter for some books that expound on color theory and color’s impact on
composition.)
SUBTRACTIVE AND ADDITIVE COLOR
Subtractive color mixing is used when the image will be seen with an external light source.
It’s based on the way reflected light creates color. Light rays bounce off colored surfaces
and are tinted by the different pigments on the surface. These pigments absorb and reflect
only certain frequencies of the light hitting them, in essence subtracting certain colors from
the light before it gets to your eyes. Pile up enough different colors of paint and you get
black; all the color is absorbed by the pigment and only black is reflected.
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