The grease combines with the stone to form a chalky soap which attracts printing ink. The ink adheres only to the greasy lines of the drawing. The entire surface is wet and the grease rejects the floater, but the water remains on the rest of the stone surface. The artist must reverse his drawing on the stone so that when it is transferred to paper it will be viewed in the proper perspective. When the drawing is complete, the lithographer prepares the stone for printing, this is a very delicate procedure.
Actual printing is coordinated by the artist and lithographer.
Lithograph proofs are always made on a hand press. Color lithography requires each of the printing steps to be repeated for each color used, as each color requires a separate stone. If there are 10 colors, there are 10 stones. Registration is extremely important. Each stone has to be registered perfectly on the paper to insure the color aligning itself in the right place.