
A glass or paper negative was created first then a contact print of that negative could be made.
Salt prints are made from paper immersed in a weak solution of common salt. It was then coated with 20% solution of silver nitrate. This creates silver nitrate crystals. These are deposited within the fibers of the paper; not held in by gelatin as was the case with later processes. The amount of silver deposited in the paper was only about one tenth the level that is found in modern prints. The negative is laid on the paper and exposed to sunlight. After exposure the image is fixed using a concentrated solution of silver nitrate.
Brown images are created but fade badly with exposure to light. Few of the earliest salt prints still exist.
George Eastman House Video Series: Salt Print or Talbot's Process