Explosions 101
By Tina Mantaring
Aaaaaand... KABOOOOOOOOOM!!!
Time stops. People gaze in awe. Everyone is silenced by the awesome display of fire and smoke and flying debris. Or at least, that's how it is when said people are watching from the safety of their seats, and the chaos is confined to the movie screen.
Indeed, explosions are a powerful tool, and not just for criminals or terrorists either. Directors use them to catch our attention, keeping us entertained and glued to the screen. Everybody loves a good explosion, and this is one area where bigger is usually better. We've seen things blow up in outer space, like the Death Star explosions in Star Wars and the exploding asteroid in final minutes of Armageddon. We've seen famous landmarks go up in smoke, like the White House in Independence Day, or the Parliament in V for Vendetta. We saw a hospital explode in Dark Knight, a hangar go up in Stealth, and, well, pretty much everything blew up in Transformers. In addition to this, all the action movie franchises like Terminator, Die Hard, Mission Impossible, and James Bond: 007 have their fair share of cool explosions.
Before the advent of hi-speed computers and powerful animation software, explosions were all done live. This meant that extra care needed to be taken in order to ensure the safety of everyone on the set. In addition to this, multiple takes could become very expensive, if at all possible. To do scenes were the full-size explosion was not possible, artists used to create miniature models of the scene, and then blow them up. Making detailed models, however, can be a painstaking process, and even with the most talented artists, you still don't get the quality that you would if everything were life-sized. Nowadays, most explosions are created digitally. That way, the actors can remain safely out of harm's way, while artists and animators have full control of the elements. They can get each and every tongue of fire to go exactly where they want it, something that isn't possible when working with real elements. Of course, there are some directors, like Michael Bay, who are famous for wanting to do things traditionally whenever they can (in the end, however, we still can't exactly blow up a planet in real life).
To make explosions as realistic as possible, they need to be decomposed first into their basic components. First, we take a look at the exploding medium. Bombs explode. Grenades explode. Rockets explode. Most things, however, will not explode on their own. For instance, unless you drill a hole in its trunk and plant a stick of dynamite inside, a tree will not explode. Neither will a sandwich, or a chair, or a refrigerator, or a person (The exception to this seems to be zombies, who sometimes have the ability to self-combust).
When the exploding medium goes off, it tends to create a shockwave that propagates outward from the center of the explosion. The bigger the explosion was, the bigger the shockwave is too. This wave is especially visible in water or in sand, or in a densely populated area, where the wave comes into contact with solids and makes them shake, or when it reaches glass and the glass just shatters. Accompanying this shockwave is the sound that the explosion makes (hence, KABOOOOM!)
In its wake, an explosion leaves behind a lot of smoke and debris. These elements are useful for emphasizing the massive damage that was caused. Another thing left in the wake of an explosion is fire. Fire is usually first visible right as the explosion goes off, and then it persists on screen as other things catch fire.
The bottom line is, explosions are cool, especially when you are in control of them. Imagine being able to be the one to push the button, and then watch as the world around you gets thrown into chaos. Wouldn't that be neat? Unfortunately, not all of us have access to as much firepower as we want. Fortunately though, there is an alternative. Thanks to the wonders of technology, we don't need powerful graphical processors and machines to create our own effects. We can do this right from our very own personal computers.
So, without further ado, I present my own little guide to creating your own (digital) explosions. The following series of step-by-step tutorials uses Autodesk Maya, and assumes that you have little or no experience in working with the software. We'll be going through all the steps needed to animate a simple explosion, and then later on, these basics can be applied to more complex scenes.