Just the lighting they gave to give it more shading, bringing out all the planes of the face.
I was struck by the simalarity of the profile with an ancient sketch of the emerald portrait Tiberius had had made of Jesus - Tiberius - Emporer when Jesus died, died himself in 37 AD - so the artist, presumably, would have known Jesus?
http://www.revealed.org/likeness.htm
"From the only authentic likeness of our Savior cut on an emerald by command of Tiberius Caesar, and given to Pope Innocent VIII from the treasury at Constantinople, by the emperor of the Turks, for the ransom of his brother, then a captive of the Christians. "
There are accounts that say his eyes were gray - sea gray...and his hair was lighter than dark brown with reddish highlights. People assume he had had to have dark hair and dark eyes because he was 'Jewish." But goodness, Jewish people, unlike say, Native American or Chinese, were not all colored the same.
There are plenty of blond, blue eyes "Jews" today and all other colors of hair and eyes - and genetics show that these traits hold true down through the ages.
So I may paint Him with sea gray eyes... ;o)
MHG - I'll try to remember to send you pic - but it may be months before I get it done - the time consuming part is getting it done in my head first -
Here's a water color I did of my kitty -
