  == si.edu images ==  You're captioning these as PD, but I think they're claiming copyright and placing restrictions: http://www.sil.si.edu/permissions/ Among other things, the images can't be put on a CD.  The copyright of the portrait painter or photographer has probably expired in most of these cases, but I think their digital image of that original painting or photograph would be copyright... if someone photographs the Mona Lisa, they can copyright their photograph even though Leonard da Vinci's work is out of copyright.   