Modeled in Cinema 4D, textured in BodyPaint and ZBrush, rendered in Cinema again with standard lights. Cinema's own Hair module has been used for adding the beard and hair. I used the Vreel Skin Shader as material. I didn't do much in Photoshop. I just did some minor color correction, DOF, added the Ambient Occlusion Pass on top if the image, tweeked the eyes and added some grain and that's it.

Render times with the Vreel Skin Shader active: 1h30min

A small WIP with some test renders and screen caps of the face textures can be found on my website [http://www.patrickeischen.com]