Concept Art. There's a set done for every costume and hairstyle used for every character in a series, with varying levels of detail. The cost associated with this is a big reason for an Economy Cast who appears in a Limited Wardrobe. If the artists wander away from it, they have gone "Off-Model".
A set of these will also exist as a guide for the model maker in a 3D CGI production.
Some typical drawings found in model sheets:
- Turnarounds: Drawings of a character from multiple angles in the same pose, usually face on, three-quarters to both sides, profiles, and rear.
- Details on particular parts of the costume or face that might be confusing on the main overviews.
- An expression chart.
- A phoneme chart, showing the ten mouth shapes needed to convey realistic dialogue and lip sync (The Preston-Blair set).
- A height comparison and scale chart. This is typically a reproduction of the front views from the turnaround for each character, with characters arranged side by side like a police lineup: common ground line, with parallel lines at the apex of each head. Typically, the main character is reproduced on each page as a yardstick. Needed to prevent wonky scale.
- Character proportions, such as a chart illustrating characters' proportions, to ensure that proportions remain consistent throughout the work.