Most of the photos on this site were extracted from reference images (high-resolution tiffs, 20 to 200 megabytes in size) from the Library of Congress research archive. (To query the database click here.) Many were digitized by LOC contractors using a Sinar studio back. They are adjusted by your webmaster for contrast and color in Photoshop before being downsized and turned into the jpegs you see here.
This is the coloration of Dorthea Lange's iconic 'Migrant Mother' photo. The stark reality of Dorthea's original photograph is actuated by the addition of color, which I think brings out detail not apparent in the black & white original. View full size.