Color photoprinting with a scanning memory mask

A color photoprinter having a scanning light source and automatic control of contrast excursion limits and exposure level is disclosed. The printer is particularly well suited to contact printing with opaque image receiving materials. A prescan of the original photographic transparency, only, is made to determine the initial exposure level and contrast excursion limits to be expected on the opaque receiving material, and to establish the required automatic exposure and dodging control signals. The original is rescanned to generate signals which represent an unsharp, luminous, contrast controlling mask. These signals are retained in a memory, such as an image storage tube. The opaque image receiving material is then moved into intimate contact with the original for the actual exposing scan, which takes place with the unsharp luminous mask electronically superimposed on the scanning light source, in order to provide automatic contrast and exposure level control of the image during the printing step. The use of combined intensity and velocity modulation to shorten the exposure time for the color exposure scan when using insensitive reproduction material is also disclosed.