(If you want it even larger than Blogger allows, get it here.)
|(Pages from the article. Click for big pic.)|
Page below is from another article, about the app Zbrush, which allows the artist to press and sculpt intuitively, like with a lump of clay, rather than with numbers and sliders. It was used for the basic head above. But notice that some even do the hair with Zbrush. There are a legion of techniques and clearly a ton of work involved in making 3D images...