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.
Tinted version of "Miss Ohio 1850" portrait found here at Shorpy. The portrait is beautiful in B&W and color was added using Photoshop "curves" function on multiple layers as a project for a Photoshop editing class. Skin tones might be a little too red for some. View full size.