Rollei/Agfa Copex Rapid is a high-resolution panchromatic black and white microfilm that exhibits very fine grain and accurate reproduction characteristics. It has a variable exposure index of ISO 50/18° to ISO 64/19°, depending on process and application, and can be developed either as a negative or a positive. Spur Modular UR (parts A and B) is the recommended developer for attaining optimal results from this film, and helps to retain high sharpness, fine grain, a wide exposure latitude, discernible tonal values, and maintained film speed from development.