Library of Congress
Loc: America's First Look Into the Camera (Daguerreotypes)
A searchable database from the Library of Congress that provides a fascinating look into the history of photography from 1839-1864. There are images from the Matthew Brady Studio and studio portraits by black photographers James P. Ball...
PBS
Pbs American Masters: Alfred Stieglitz
A comprehensive site about Stielglitz's historic role in the field of photography. Historically significant photos and documents.
Pennsylvania Historical and Museum Comission
Explore Pa History: Robert Cornelius
A concise biographical sketch examining the life and contributions of early photographer and Pennsylvania native, Robert Cornelius.