Although the term can refer to commercially reproduced images, such as those on posters or in magazines, at Tamarind a lithograph is an image made by an artist who works closely with an artisan printer. There are many different kinds of prints, including reproductions made from an image that already exists. Some artists print their images themselves. Others work collaboratively with a skilled printer, who discusses ideas and materials with the artist, and carries out all the technical requirements such as processing and printing. In each case, what distinguishes the print as original is that the artist participated directly in the creation of the image and approves all impressions.
Lithographs differ from etchings, engravings, serigraphs, and woodcuts in materials and process.
As opposed to many other print processes which depend upon incised or carved lines, lithography is a planographic process that depends upon the mutual repulsion of grease and water. For example, etchings and engravings are printed from a metal plate with incised lines while a lithograph is made from a chemically treated, flat surface. A serigraph is a silkscreen print, and woodcuts are printed from blocks of wood carved in relief. To make a lithograph, the artist first draws an image, in reverse, on a fine-grained limestone or aluminum plate. For a one-color lithograph, this will be the only drawing.