In offset printing the colors are output on separate lithographic plates.
Take a lithographic plate and etch three marks on it.
Richter produced about 3000 lithographic plates and watercolours for his employer.
The series eventually grew to 31 parts, taking until 1973 to complete and containing over 1300 lithographic plates.
This film is then burned onto a lithographic plate, using a plate burner.
The whole series has 63 volumes with 1677 lithographic plates (more than 900 of which are in color) depicting 18,587 subjects.
For this last volume Meigen had to make the lithographic plates himself to cut expenses.
It was probably he who drew directly on a couple of the photographs at Zabriskie before copying the images onto the lithographic plate.
The next day they arrived at the printers with 32 collages, which were transferred to lithographic plates.
Most of Gould's work were rough sketches on paper from which other artists created the lithographic plates.