Abstract: Methods and apparatus are provided for producing a set of color correction masks on a single piece of masking film, or a set of color separation negatives on a single piece of separation negative film. The set of masks or set of negatives may be exposed so that each entire set may be developed simultaneously under identical development conditions. This is accomplished by determining a development time which provides substantially identical or other desired contrast indices for all of the masks or negatives in a set. The exposure time required for each mask or negative in the set is then determined so that the color components of the exposures will be balanced in the manner desired when the exposures are developed for the predetermined development time. The exposures may then be made in the apparatus provided for that purpose.The apparatus of the invention includes means for rotating a slide transparency and an opaque shield to expose four quadrants of a single piece of film in sequence.