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 (contone for short, or CT even shorter) is one where each color at any point in the image is reproduced as a single tone, and not as discrete halftones, such as one single color for monochromatic prints, or a combination o ...

copy, one through a halftone 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 Positive is a property of positivity and may refer to: Mathematics and science * Positive formula, a logical formula not containing negation * Positive number, a number that is greater than 0 * Plus sign, the sign "+" used to indicate a posi ...

, 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.

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