Every time I see The Dark Knight, I am surprised when looking at the makeup of Harvey Dent (Two Face). What kind of technology is used in such make ups and how are they done? The makeup was really scary. Especially the way his eyeball and jaw are shown! Here is a picture for a quick recap:
Sort answer: It was a mix of make-up and CGI.
Long answer:
For Two-Face, Nolan decided to break new ground. "This character was one of our major vfx challenges," recalls overall Visual Effects Supervisor Nick Davis. "Chris was not interested in going the traditional make-up route. He felt that it would be an additive effect, rather than the subtractive effect that he felt the character required. So, instead of adding a layer of material to the actor's skin, we actually removed the skin digitally. It allowed us to reveal the tendons, the cheeks, the eyeballs and to create unique textures. The challenge here was that we were dealing with one of the main characters, and that the digital make-up would be seen in full close-up, including in dialogue scenes…
Framestore's White notes that the key to the Two-Face project was to get enough detail into the CGI to give it realism. "In doing so, we worked at much higher texture resolution than we normally use. We also rendered our CG work at 4K, even for the regular 2K anamorphic shots. A very large number of texture layers were needed, and displacement maps from Mudbox were combined with bump maps and displacement maps painted in Photoshop. It really took a significant amount of work to get it right."
The full details are explained here.
