Handwork on engravings and lithographic screened (halftone) negatives for correcting tonal values in either black-and-white or color work.
Chemically reducing halftone dots to control the amount of colour to be printed. Dot etching negatives increases colour; dot etching positives reduces colour.
The process of chemically reducing halftone dots in film negatives or positives to increase or decrease the amount of color to be printed.
In lithography, the chemical etching of silver halide halftone emulsions to increase or reduce the amount of color to be produced. Dot etching negatives increases color; dot etching positives reduces color.