Woodbury and Lippmann: A new approach to continuous tone and full colour non-impact printing

A historic development, the CMYK halftone process and the ruled glass screen patented by Frederick Ives, has led to the reproduction of almost all present day images as pixelated CMYK prints. Historic processes, such as those invented by Woodbury and Lippmann produce prints far superior to anything which is commercially available at the present time. Those processes have been largely forgotten as they were not commercially competitive. Woodburytype was the first, and still is the only photomechanical process that can reproduce truly continuous tone. A topographic print of pigmented gelatin layers, the image is generated by the absorption of light in those layers. Lippmann photography does not contain any dyes or pigments, but still reproduce the biggest colour gamut possible on the basis of interference colours. Light is selectively reflected by resonance cavities which makes the photograph change colour under different viewing angles. In classic Lippmann photography, the reflective layers of the cavities consist of very fine metallic silver grains separated by layers of gelatin. Woodburytype and Lippmann photography and their 21st century incarnations will be discussed.