This took about an hour, and my rule was DON'T sample any colours from the reference photo (I do that far too much). It's Bertrand Russell by the way...:)
OK, so I wanted to do caricature of Robert Downey Jr. reminiscent of a portrait, and then I thought about traditional old portraits of men in suits of armour... a quick google found me a pic of a painting with the right feel: And so this is the sketch for Ye Olde Iron Man pic:
Saw this film a couple of weeks ago and thought it was great. I really wanted to do a pic of Clint Eastwood from the movie, he's got an amazing craggy face now and an 'old man walk'. Looking forward to painting this on board or canvas.
EDIT: Updated with a newer version - added some more elements to the background.
Still working on it - after correcting a problem I stepped back and looked at the original sketch which is after all what I wanted to transfer to this larger format - and I could see a lot of areas that had drifted away from what I wanted. I've made a lot of small changes to the face to drag it back...