Idea
Many of the employees at Pixar scuba dive or have a deep love for the ocean. When it was time to pitch a new idea for a movie, Andrew Stanton took his idea to the head of the studio.
Concept
Once the okay was given to start the project, teams were assembled to conduct research in order to make the characters and environments as realistic as possible. Animators took trips to aquariums to study how fish moved and interacted in their environments. When designing the characters, the team had to figure out how much they wanted to characterize the fish. Since fish are exaggerated in real life, the creators had to be careful with proportions and style. They decided to exaggerate the eyes and mouths more than anything else. Dog's facial expressions were studied to create expressive features. Another challenge that the designers faced was making the characters look appealing since, in real life, fish are slimy and smelly. The team was able to achieve appealing characters by creating three types of fish: gummy, metallic, and velvety. Every character fit under one category and had it's own specific process.
Sound
At the same time as the concepts and storyboards were being drawn up, recruiters set out to look for voices to bring their characters to life. Once the cast was set, recording begun. The animators then use this audio to fit the characters movements too. Music is also scored. These pieces add atmosphere to the scenes and aid animators in timing and screenplay.
Animation
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