Colouring the base [or the emulsion side] by applying a coloured varnish.

This system was used in laboratories before pre-tinted positive printing film was introduced on the market. There is little information on how this was carried out. Examples seem to be discretely painted or sprayed on one side only. The description in the Agfa processing manual of about 1925 indicates that coloured lacquers were applied by roller to the image area between the perforations, of the film base, but film of this character has not been reported to the Editor. It seems that this technique was very uncommon.

Several film archive specialists have recently experimented with this procedure using some form of air brush to spray dye onto uniformly moving processed prints and the authors expect this system to be used for making modern reproductions of coloured films at some time.