The introduction of silver nitrate gave the prints their warm, chocolate brown color. Salt prints are the most modern of the three photographic processes. As the name suggests, the prints are made by the incorporation of table salt in the process and the prints have more contrast and a shorter range of tones. As they were used in the infancy of photography, they were practiced for only a couple years before the next method came along. Using the oatmeal boxes as pinhole cameras creates a distorted image due to the extreme wide-angle of the pinhole and the curvature of the box of oats.
Photographic paper is inserted into the boxes, which are left in the sun for exposure.
The use of pinholes in creating art was employed by pictoral artists such as Dutch painter Jan Vermeer. These early ways of reproducing an image must certainly have been trying for pioneers in photography. The paper negatives can sometimes take hours to expose and exposure times vary depending on the amount of available sunlight on any given day. Segal said the techniques, however, have helped the students learn craftsmanship. Jeremy Dean agreed.