What is indicated by a straight white border on a radiographic film?

A straight white border on a radiographic film is indicative of developer cutoff. This occurs during the film processing stage when part of the film does not come into contact with the developer solution. As a result, the area that is not developed remains unexposed and appears white on the film. The sharpness of the straight border often signifies a clear demarcation between the developed and undeveloped areas, which further supports the identification as developer cutoff.

In the context of the other options, incorrect film processing typically results in various artifacts or overall poor image quality rather than a clear straight edge. Overexposed film would present as a uniformly dark image without a distinct border, indicating that light-sensitive crystals were too fully developed due to excess exposure. Inadequate developer temperature could lead to an overall underdevelopment of the film but does not specifically create a straight white border.