The eyes of cartoon characters in movies are often cheated so that the sclera has only a slight form shadow, almost no ambient occlusion and stays more evenly lit across its surface and accross both eyes. It’s not 100% of the time, it depends on the scene but very often it looks like it.
Below are some image examples that seem to cheat the lighting according to me.
I’ve heard that these tricks can help it :
[li]flattening the eye with a lattice
[/li][li]having enough SSS in the eyelids to prevent too much AO on the sclera
[/li][li]increasing the brightness of the eyes in compositing using the object ID of the eyes
but do they also sometimes mix the eye’s realistic shader with a shadeless shader ?
I mean, look at Violet, her screen right eye is partially under her hair, and it looks just as bright as the other eye.