Stone Lithography
Stone lithography was the first printmaking technology that allowed a traditional artist to work using traditional techniques, and to create prints that could rival an original painting in terms of detail, mood and color variations. Stone lithography was extremely popular starting in the early 1800s, and even though more modern methods have replaced the majority of its uses, it is still practiced today by some artists and lithography studios.
The basic idea used in stone lithography is extremely simple:
1. The artist draws/paints on the stone with a greasy substance. For example, a litho crayon is a soft waxy/greasy crayon. There are also litho paints and pencils. The stone picks up this greasy substance and holds it.
2. The stone is moistened with water. The parts of the stone not protected by the greasy paint soak up the water.
3. Oil-based ink is rolled onto the stone. The greasy parts of the stone pick up the ink, while the wet parts do not.
4. A piece of paper is pressed onto the stone, and the ink transfers from the stone to the paper.
For a wonderful article that shows step by step examples of the process of stone lithography, see How Stuff Works
Stone lithography was used heavily during the early years of cinema. Several changes to the lithography industry caused the elimination of the use of this process.
Large slabs of limestone had to be used which were extremely heavy and bulky. The majority of these were imported from the Limestone pits of Bavaria. The bombing of World War I destroyed a large number of limestone pits, so an alternative had to be found for a large number of lithographers.
Some of the major lithographers turned to using a zinc plate instead of the limestone from necessity. Even though it gave the final image a slightly grainier look, it became the dominant printing process in the U.S.
By the late 30's, another major change was in the works with the movement to offset presses. This process is VERY distinguishable from the stone lithos.
Since lithos using zinc plates were not marked any different, most collectors consider these posters as stone lithos.
Original article here:
http://www.learnaboutmovieposters.com/newsite/index/articles/StoneLithography.asp
