Polishing of my shot.
This week has been an interesting learning experience. Becoming ever more fascinated regarding the relationships within the facial structure.
Expressions like rage and mad/anger, may seem pretty similar. However, if the frontalis pushes the brows down when angry, why do they appear to be lifting for rage (something which would require the occipital belly)?
Mike Safianoff summarized it as the following:
Expressions work in a series of progressions. Think of it similar to verbal communication. Rage is a louder version of mad, but the face can't get louder, so the only way to show MORE anger is to get more muscles involved. The occ pulling back, the frnt coming forward, and the corg down, combined with sneered lips/raised nose for disgust, compression around the eyes and an open jaw creates rage. Anger is isolated to just the occ, frnt, and corg...with maybe a little asym sneer in the mouth or the lips rolled in (no teeth).
So the more intense the facial expression, the more muscles we may use to communicate.
Though a detailed understanding of muscles is not necessary to animate the face, it certainly helps, especially with the mixed messages that surround particular workflows.
In an old video series, it was told that the inner brows lead the action. Considering the positioning of the frontalis, this advice seems rather odd. If the inner brow was to lead, surely it would depend on the activity of other muscles, such as the currogator. For confirmation, I quizzed Mike on this:
The brow is very much a combination of muscles and should be treated as whole. There are times when a muscle group fires first or is more prominent in a move but it all depends on the situation. But its important to remember any time one muscle group fires it has an effect on the others...everything is connected.
Lastly, here's a link to an interesting resource: http://www.artnatomia.net/uk . It shows the action and range of each facial muscle.
Posted by steven hawthorne