This part of ISO 9236 specifies methods for determination of the sensitometric curve shape, average gradient and speed of a single sample of a screen/film/filmholder/processing system in mammography. The filmholder may be any means which ensures close screen/film contact and prevents the film from being exposed to ambient light. In particular, the filmholder may be a light-tight vacuum bag, as often used in the laboratory, or a radiographic cassette as used in mammography. NOTE — Hereafter, screen/film/filmholder combinations will be referred to as "combinations", and will be referred to as "systems" when the processing is included.