Copper Photopolymer: Step Three – Exposure (Hand Drawn Method)

Posted on: September 27th, 2014

Exposing (drawing, photograph)

The exposure time for a drawing on the thin frosted Mylar (sold in the tool shed) is 4 units for the drawing, followed by 12.5 units for the aquatint screen. Post-exposure time is 16 units (this occurs after you’ve developed your plate).

Lift the exposure unit lid with both hands, place plate, blue side up, on the bed of the exposure unit (make sure that the protection film is still on the photopolymer). Put your drawing, drawing side down on top of the copper plate. We call this EMULSION to EMULSION. This term refers to the ink/material of the drawing touching the substance that the drawing is being transferred to. Photopolymer film is a “right reading” process. This means that you don’t have to flip your image, or write things backwards. Close the lid and secure the lock. Turn on the vacuum, wait until the vacuum is fully engaged, set the units and press start. Once done, take the drawing out and replace the drawing with the aquatint screen. Close the lid, secure the lock, turn on the vacuum, set the units, and press start. Once finished you’re ready to develop your film.

The exposing time for photographs is 16-18 units. You do not need to apply the aquatint screen, as the Epson printer puts the necessary dot pattern on your film. Open the lid of the exposure unit. Place your copper plate, blue side up, on the bed and put your photograph, ink side down, on top of the copper plate. Close the lid, turn on the vacuum and set the units. Once the photograph has been exposed, the plate is ready to be developed.

Drawing ONTO the film directly with developer

Developer can be used in different strengths as a drawing medium – the stronger the solution or the longer you leave it on, the darker the affect. The marks resemble the traditional etching technique called spit-bite. In our shop, we have mixed solutions in the following ratios 1:10, 1:25 and 1:45 (soda ash to water). First expose the aquatint screen onto your coated plate, using an exposure time of 12.5 units and remove the protective layer of plastic (a small piece of tape applied to the corner helps to get it off). Set up a water tray, a spray bottle of fixer (diluted vinegar), a few brushes and the different developer strengths. Paint the developer directly onto the film, wait and rinse with water. The water will stop the development, allowing you to work slowly, work back and forth from the water tray to painting. Once you are satisfied with the image, spray fixer onto the plate and rinse with water. Post expose for 16 units and print.

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