Painted, tweaked a bit. This has been an interesting sculpt to do. Rather experimental, very open to interpretation. I'm sure it's the end-all, be-all method of critique to look for Heath Ledger in there. Between the make-up and his great performance (what I've seen) I do not see Heath Ledger in that character at all. He really pulled a Gary Oldman with this one. And far as what Heath might look like screaming insanely? Who knows? It's gonna take away a lot from the face we're all used to seeing. An extreme expression is going to distort a person's entire face. Go give it a try
look in the mirror a few seconds, then make a crazy face and look again. You'll be surprised how much that other guy
doesn't look like you. I had to watch A Knight's Tale and look for frames where he was angry, or yelling to find a few characteristics of his face in that pose. Then I had to combine that with the Joker make-up. I also factored in how those scars might affect facial muscles.
I'm not makin excuses to defend the work, I knew it was rather speculative when I started it. Sculpting study/theory is as much fun to discuss as it is to practice. I think that's why I wanted to do it, the guess work. The only solid stuff I had, the stuff we're all very familiar with, was the make-up, scars and hair.