``Dante's Peak'' How was the powerful disaster scene created in an era when CG was underdeveloped? (Part 2)

Representation of lava flow

Harry and Rachel head to her house to rescue her two children. However, the children drive to the mountains to help their ex-stepmother Ruth (Elizabeth Hoffman), who lives in a house in the mountains. Harry and his friends follow and barely make it to Ruth's house. But Ruth stubbornly refuses to go down the mountain.

However, a lava flow hits Ruth's house, and the five escape on a boat to the lake. However, the lake water has become strongly acidic (*7), and a hole appears in the metal boat and it begins to flood. The propeller had also melted, and the boat could no longer move, so Harry began rowing with his hands covered by his jacket. However, just as they are about to reach the shore, the boat begins to sink. Feeling responsible, Ruth jumps into the water and pushes the boat to shore. However, she suffered severe burns and died on the way down the mountain.

McClung originally planned to use physical effects to represent the lava flows as well. Methods such as using fluorescent paint (*8) were tested, but they were quickly abandoned and it was decided to express the whole thing using CG. In the current CG industry, Houdini , manufactured by Side Effect Software, is widely used as an effects tool to express natural phenomena. However, it was not released in time when this work was being produced. Therefore, Digital Domain's development staff developed a tool that can express highly viscous fluids based on Houdini's previous generation, Prisms. For the lava texture, I wrote my own shader using Pixar Animation Studio's RenderMan software. In the end, it took 10 months to get the OK, but we managed to get there in time.

"Dante's Peak" (c)Photofest / Getty Images

The scene where lava breaks through the wall of Ruth's house and the five people escape was the most difficult scene for the staff. Cinematographer Andrzej Bartkowiak filmed the actors' actions on a Steadicam set in a house built in Wallace. Digital Domain staff accurately recorded the shapes of buildings and terrain in order to match the CG lava flow here.

Back in Los Angeles, the crew tracked the footage, determined camera motion, and motion-controlled the set at the Van Nuys Airport. During this process, each wall and piece of furniture in the house was photographed separately and broken down into 36 layers. The first-ever digital lava flow was created by compositing the materials extracted from the original plate, the forest and lake in the background, flames, smoke, and other elements extracted from the original plate.

*7 In fact, a terrifying acidity of pH 0.5 has been observed in the crater lake of Mount Ijen in Indonesia.

*8 In `` Volcano '' (1997), artificial lava was mixed with mesocel (methylcellulose), which is used as a food thickener, a low-foaming surfactant, and red, orange, and yellow fluorescent paint. It was created by pouring it onto a transparent acrylic board and illuminating it with a black light from below. Any cracks in the surface were sprayed with black lacquer (this analog method was so effective that it was used in Star Wars: Episode III: Revenge of the Sith (2005)). However, CG lava is also used in the pull shot.

mudflow scene