The polymer plate is twice exposed to uv light — once in contact with an aquatint screen (a stochastic, or random patterned screen producing a similar effect to a halftone) and then to the image positive.

Available on backorder

I have been using these fine-micron stochastic screens both for my work in polymer photogravure, and in the workshops I teach, for many years. They produce a full range of tones and contrast. If necessary, the screens can be cleaned with a soft cloth and film cleaner (PEC-12) or isopropyl alcohol.