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How Industrial Light and Magic Works


Putting it All Together
A shaded version of the Andrea Gail
A shaded version of the Andrea Gail
Photo courtesy of ILM

Once the basics have been blocked out using the simulation and particle systems, all of the details are planned out. This is what makes the difference! Without all these exact details in place, the shot would look realistic but would still feel wrong, causing you to realize intuitively that the scene was using CG effects. You have probably seen this in other movies -- maybe the shadows were not quite right, or the coloration of the CG portion didn’t exactly match the real part.

It is amazing to look at all the different layers that ILM created for each shot:

The colored and textured version of the Andrea Gail
The colored and textured version of the Andrea Gail
Photo courtesy of ILM
Close-up showing the CG actors and buoys
Close-up showing the CG actors and buoys
Photo courtesy of ILM
The simulated ocean. Note that the boat's movement in this ocean must be completely matched to the wave motion to be realistic.
The simulated ocean. Note that the boat's movement in this ocean must be completely matched to the wave motion to be realistic.
Photo courtesy of ILM
Run-off from a wave crashing over the boat in an earlier frame
Run-off from a wave crashing over the boat in an earlier frame
Photo courtesy of ILM
A wave of particles created by the boat's movement in the water
A wave of particles created by the boat's movement in the water
Photo courtesy of ILM
The splash created by the boat crashing into a wave
The splash created by the boat crashing into a wave
Photo courtesy of ILM
The boat's lighting model
The boat's lighting model
Photo courtesy of ILM
One frame of the final shot with all of the elements integrated together
One frame of the final shot with all of the elements integrated together
Photo courtesy of ILM

In the all-CG shots, nothing else needs to be done. But many of the shots combine CG and live action. Most of the live action was filmed in a water tank with a blue screen surrounding it, on Stage 16 at Warner Bros. Studios (the largest indoor tank in the world). The blue screen has a grid of red dots in white squares, called targets on it, which are used to align the virtual camera’s viewpoint with the live camera. Most of the targets had to be removed manually frame by frame, making for a long and arduous process.

The CG elements are color-corrected and blended with the live footage. Some scenes require a little CG sleight of hand -- adding CG waves or swells -- to mask unwanted live elements. Additional mist and foam patterns are composited onto each frame. Finally, all of the live and CG elements are composited together to form the complete shot.

The shots are edited together and the film is released. You go to the theater, or you rent the VHS or DVD release of "The Perfect Storm," and you are stunned by the most amazing and realistic weather effects ever created, unable to tell what is real and what is computer-generated. And that is the greatest compliment ILM could ask for.