The Dultgen halftone intaglio process is a photoengraving technique invented by Arthur Dultgen and is widely used today in commercial colour work. Two positives are made from the

continuous tone A continuous-tone image is one in which each color at any point in the image can transition smoothly between shades, rather than being represented by discrete elements such as halftones or pixels. Examples of continuous-tone images are natur ...

copy, one through a

halftone Halftone is the reprographic technique that simulates continuous tone, continuous-tone imagery through the use of dots, varying either in size or in spacing, thus generating a gradient-like effect.Campbell, Alastair. ''The Designer's Lexicon''. ...

screen or a special contact screen and the other without a screen. A sheet of carbon tissue is then exposed first to the screened positive, which produces an image of dots of varying sizes, then to the continuous-tone positive, which produces differing degrees of hardening of the dot image. The array of dots vary not only in width but also in depth so as to extend the range of tonal values to be reproduced. This method thus uses two methods for controlling tonal values.

References

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