valokuvafilmin
Valokuvafilmi, often referred to as photographic film or simply film, is a transparent strip or sheet material coated on one side with a gelatin emulsion containing light-sensitive silver halide crystals. When exposed to light, these crystals undergo a chemical change, forming a latent image that can then be developed into a visible photograph. The process relies on the principle of photochemistry, where light energy triggers a reaction within the silver halide.
The film base, typically made of cellulose acetate or polyester, provides a stable support for the emulsion.
Historically, film was the primary medium for capturing images before the widespread adoption of digital photography.