Definitions for "Amberlith"
amberlith area appears black to the camera, and prints clear on the resulting film, red-orange acetate is used for masking mechanicals to be photographed for plates.
An orange plastic sheet, placed over a pasted-up page, that contains shapes that the printer needs to screen, overprint or print in another color.
(Brand Name) - A red or orange material for preparing art and dummies. Transparent to the eye but appears opaque to light sensitive materials.
an example of the extensive range of supplies carried by this vendor