Enlighten Me

Lighting has been used to enhance emotion and appeal of characters for centuries, from paintings in the Renaissance to the modern-day digital arts. In VFX and animation studios, lighting is considered as important as modelling, shading, or rigging. Most existing work focuses on either empirical best-practice created by artists of the centuries or on lighting perception with basic shapes. In contrast, our work focuses on the effect of lighting on emotional characters. Our study presents an extensive set of novel perceptual experiments designed to investigate the effects of brightness levels (key light brightness) and the proportion of light intensity illuminating the two sides of a character’s face (key-to-fill ratio). We are particularly interested in the effect of lighting on the recognition of emotion, emotion intensity, and the overall appeal, as these are crucial factors for audience engagement. Our results have implications for artists and developers wishing to increase the appeal and emotional expression of their characters, ranging from cartoon to realistic styles. Our key finding is that lighting can be used to effectively alter the intensity of emotion of a character and that brighter conditions increased appeal across all of our experiments.

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