Which layer of film base acts as the protective covering?

The supercoat serves as the protective covering for the layer of film base. It is typically made of a clear, resilient material that safeguards the sensitive emulsion layer beneath it from physical damage, scratches, and environmental contaminants, such as dust and moisture. The supercoat ensures that the film can be handled and processed without compromising the quality of the recorded images.

The base provides structural support for the film but does not act as a protective layer; it is primarily functional for holding the emulsion and supercoat together. The emulsion is the light-sensitive layer that captures the image when exposed to light, while gelatin is a component of the emulsion that holds the silver halide crystals. Each layer has its distinct role in film production and development, making the supercoat essential for protecting the emulsion layer vital for image capture.