notch code
n.PhotographyAn pattern of shallow indentations cut in the edge of sheet film and used to identify the type of film and which side is light-sensitive.
Notes
The pattern used to create a notch code may include a combination of one or more shapes that are square, round, triangular, or scooped. Notch codes are not unique; the same pattern may be used by different manufacturers for different films, and the same manufacturer may recycle a code. The code is also used to help photographers correctly load film into holders in the dark. When holding film with the notch code in the upper right corner, the emulsion is on the upper (facing) side.
