With the glass panel device the artist drew on a glass pane provided with a wooden frame. The drawing was made with a brush and black solder, a enamel used in glass painting (contains gum arabic
as a binding agent).
Dürer used a very fine pointed brush for the drawings.
In order for paint to adhere to the glass, some painters also coated the glass completely with rubber water (= gum arabic diluted with water). They then drew with a pointed red chalk pencil.
Other sources also report the use of red chalk pencils in combination with a coating of beaten protein to allow the abrasion of the pencil to adhere to the glass.
From this drawing on the glass plate, a pause was then made on oiled paper or the drawing was transferred directly onto real drawing paper by placing the drawing paper on the glass and holding it against the
light.
Woodcut by Albrecht Dürer
Now one could trace the drawing with a pencil, for example. Afterwards the drawing was possibly further processed with drawing pen and ink.
Oiled paper:
In earlier times, oiled paper was used as transparent paper. Oiled paper is obtained by coating the back of a drawing paper with oil (linseed oil, olive oil, etc.), wiping off the excess oil with
a cloth and allowing the paper to dry in the sun. It was also sometimes worked with a pumice stone.
Glass panel with improved sighting device
Woodcut by Albrecht Dürer
Glass panel device with perspective point transfer device
Woodcut by Albrecht Dürer