Primitive Photography

❺

Salt Prints by Development

Having acquired an understanding of the procedures involved in making paper negatives, you are now in position to apply these procedures to making positive prints. With regard to photographs made during the calotype era, one usually has in mind a positive technique known as salt printing. Salt printing received its name from one of the chemical ingredients, sodium chloride, or common table salt. Most early salt prints were made by a process known as printing-out, whereby a positive image was made by laying the negative face down upon another sensitized sheet of paper and exposing the sandwiched combination directly to sunlight until an image was formed.¹ By the 1850s, another kind of salt-printing process existed, ...