Directions: Read the passage, and answer the question that follows.
Inevitably, successful action movies have special effects that “wow” their audiences. A tornado is one type of special effect that can be impressive. In real life, these wind monsters attract many people’s curiosity. The high-speed spinning of tornadoes can cause great destruction. So, it isn’t surprising that these destructive forces on the big screen can make or break a movie’s popularity.
It is risky for moviemakers to tackle weather as part of a big-screen project. Nobody does it better than Mother Nature, right?
Dorothy’s “Ride” to Oz The movie The Wizard of Oz was released in 1939. Most people are familiar with Dorothy’s journey to the magical land of Oz. The tornado thrilled audiences as it swept Dorothy’s house out of Kansas and into Munchkinland. The movie’s technical details were considered quite high-tech for the 1930s.
The moviemakers wanted the tornado to look realistic. It took several tries to get the tornado to look right. The original twister was a 35-foot-tall rubber cone. However, the material was too stiff. Adjustments had to be made so that it would appear more natural. The special-effects person tore it down quite a few times. Eventually, he was inspired by windsocks. These simple weather instruments are made of tubes of fabric attached to the top of a pole. When the wind blows, the fabric points in the direction that the wind is blowing. The improved tornado was made of cloth. This new 35-foot wind monster was very flexible. It could move from side to side, bend, and twist—just like the real thing!
Now the special –effects person needed to figure out how to make the twister move. A steel framework was hung from the stage’s ceiling. The top of the fabric cone was attached to it. This framework could move across a wide stage. It allowed the tornado to cover large distances. The bottom of the tornado was hidden in a slot on the stage floor. A long pole was inserted through the bottom end of the cloth cone. The pole was used to move the twister from side to side. People at the top of the cone pulled it in one direction, while others are the bottom moved it in the opposite direction. The combined actions made the tornado appear to move back and forth.
Other adjustments had to be made to make the tornado appear realistic. To prevent tearing, a thin wire was woven into the bottom of the fabric. Next, powdery brown dust was sprayed into the fabric cone. The dust made the tornado appear less solid. The dust seeped through the fabric to create soft, blurry sides for the tornado. Then, clouds of yellow-black smoke were puffed onto the set from above. The smoke completed the realistic appearance of the tornado. Finally, this twister was ready to take Dorothy away from Kansas!
Computer-Generated Tornadoes
It has been very difficult for special-effects crews to figure out how to improve upon the tornado in The Wizard of Oz. It is considered to be a special-effects masterpiece. However, modern audiences have become much better at detecting what is real and what is fake in movies. The creators of the film Twister wanted their tornadoes to appear as real as possible, too. They decided to use computer-generated or digitized, tornadoes. To find out what a computer-generated tornado would look like, a test shot was developed. This “test twister” represented a large, black tornado throwing out dirt and a large tractor tire. It took 10 weeks to create. The director was very happy with the results. It was used for the movie’s advertisement.
Actual filming for Twister began in 1995. Computer crews developed software programs to make the tornadoes realistic. Using computer technology, the behavior of a single object could be changed. For the first time, it was possible to light particles such as dust from different angles. The shading and movement of the twisters in this film were more realistic than anything done before!
Animators were able to create realistic digitized tornadoes of various sizes. The size and strength of a real tornado are judged using a Fujita scale, or F-scale. The least destructive tornado is classified as an F1. The most destructive is an F5. Animators created virtual tornadoes F3 and smaller by using solid cones with added layers. The layers shaded part of the tornadoes, making them appear more realistic. Larger tornadoes needed to appear more solid. Therefore, many layers of debris were added. Animators were also able to spin larger tornadoes slowly, just like real tornadoes move.