[xaedes]

What about the "Maybe try rendering an image of a 3d model of a face, then attempt to reconstruct it from the rendered image and measure the displacement from the original model." approach for generating high resolution training data?

[ralusek]

That's actually a great idea. Because then you can get a diff between the outputted 3d and the actual 3d used to generate the images, as opposed to what I assume is just diffing the generated profile with a profile shot of the subject.