This was accomplished by filming water pouring down two sides of a U-shaped tank and then running the film backwards, making the water appear to divide. Keeping the walls of water apart, however, while the Israelites walked through, was much trickier. The real Kong was a puppet 18 inches high with a metal skeleton covered with foam rubber and rabbit fur. Kong's fur was pushed down every time animators handled him, and his skin appears to ripple as a result. The Rains Came spared no expense to create an earthquake, a breaking dam and flood, and a collapsing temple.
Many movies rely on several different techniques to produce an important effect.
For example, Jurassic Park used a mix of animatronics, puppets and computer animation to create its famous dinosaurs. In what is one of the most complex special effects sequences attempted, the massed forces of the Rebel Fleet take on the Death Star at the end of Return of the Jedi . Legend has it that among the hundreds of ships in the shot are a sneaker and a few sticks of gum. The sequence shows the T-1000 morphing into a succession of human forms that it has assumed earlier in the movie. Over 800,000 hours of number crunching went into the final film, which works out to more than a week of computer time for every second on the screen.