Now that I am happily married, I start to gain momentum and motivation in returning to and working on Ara’s Tale.
I totally underestimated the challenge of rigging the face. Its very demanding, both technically and artistically.
Based on my research my first naive approach was to set up some bones for the areas of the mouth, brow and cheeks and play with the weight painting. That way led to frustration. Coincidently the Durian team ( more precisely Nathan Vegdahl ) posted on their blog, that he abandoned a bone based rig and returned to a shape key based one.
Following this, there was also a very informative thread on blenderartists about ways to rig a face.
I did a step back and considered the situation. My rig should just do what the storyboard showed me it should do, no more, no less. So no need for a generic rig with a full expression range. I started anew and created several shape keys based on some basic expressions found at the artnatomia site. Only the jaw is bone deformed.
I ended up with 3 shape keys for the brow area, 3 for the mouth area one for the cheeks and one for the lower eye lids. I hooked all the shape keys to control bones in my rig and started playing and tweaking.
I still have some problems with the mouth area, but I think the system I have now will fit my needs.
Initially I thought it necessary to create higher level actions for basic expressions, but after playing around a little bit I think I will use the bare controls for the moment.
See here for a sequence of images where Ara goes through a series of expressions. This is all done with the shape key system combined with the already in place (bone driven) eye rig system. Its only greyscale since GIFs can only display a 8bit palette based images and the color version has some serious color banding.
I may still tweak the shape keys and even may add some more, but the moment is nearing when production is finally starting, meaning the animation phase will start in earnest and I will start with the first shot to animate.