Pyrotechnics: Fire, Explosions, Energy Phenomena
501
The need for debris is one reason that exploding miniatures are still in use (or even, when possible, full-scale
explosions).
The debris cues viewers to several important pieces of information about the shot. First of all, how big was the
explosion? The slower moving and bigger the amount of debris, the bigger it probably was. For this reason,
effects pyrotechnics tend to use miniatures shot with a high-speed camera. The resulting slow-motion effect
makes the explosion seem much bigger than it was.
If your shot calls for a chunky explosion and you dont have any chunks in your source, you need to add them
somehow. Many 3D programs these days include effective dynamics simulations; if you go that route, be sure
to generate a depth map as well because each chunk will only be revealed as it emerges from the fireball. Many
other concerns associated with this are beyond the scope of this discussion because they must be solved in
other software.
One effect that seems to come close in After Effects is Shatter, but its hard to recommend this unless it is
specifically a pane of glass or other plane that breaks. Shatter isnt horrendous for a decade-old dynamics
simulator, but its primary limitation is a huge one: It can only employ extruded flat polygons to model the
chunks. A pane of glass is one of the few physical objects that would shatter into irregular but flat polygons, and
Shatter contains built-in controls for specifying the size of the shards in the point of impact. Shatter was also
developed prior to the introduction of 3D in After Effects; you can place your imaginary window in perspective
space, but not using a camera or 3D controls.
A wide selection of pyrotechnic explosions is also available as stock footage from such companies as Artbeats.
In many cases, there is no substitute for footage of a real, physical object being blown to bits (Figure 14.23).
Figure 14.23. Pyrotechnics footage is just the thing when you need a big explosion, filled
with debris. (Images courtesy Artbeats.)
In a Blaze of Glory
With good reference and a willingness to take the extra step to marry your shot and effect together, you can
create believable footage that would require danger or destruction if taken with a camera. Even in cases when
you work on a project that had the budget to actually re-create some of the mayhem described in this chapter,
you can use the After Effects techniques to enhance and build upon what the camera captured.
And remember, be careful out there.

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