I found this image online today. It is made of 1000 images of Jesus Christ. It is in the Public Domain. I am hoping you will be able to save this and blow it up in order to see the method. I thought this astounding, so posted it here. It is taken from the "oldest known icon of Christ Pantocrator, encaustic on panel (Saint Catherine's Monastery, Mount Sinai)."
This is the original icon, Christ Pantocrator, found at wikipedia.com.