Abstract: A simplified method for producing a smoothly graduated, three dimensional engraving in a substrate using a shotblast resist. The method includes preparing a continuous tone transparency having various levels of tone which correspond to the varying levels of depth required in desired image to be engraved into the substrate. A resist film is then contact exposed through its film base and through the continuous tone transparency of the image to an actinic source of electromagnetic radiation for a specific quantity of exposure and the varying levels of radiation transmission through the various tones of the transparency result in a controlled differential exposure of the resist film. This correspondingly results in progressive hardening and toughening through the resist film from its film base according to the various levels of actinic radiation to which it is exposed. The unhardened areas are then washed out and a resist having a smoothly varying thickness is thus produced.