Film reels work by capturing light and storing visual information on a strip of plastic film coated with a light-sensitive emulsion. Here's a breakdown of the process:
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Film Structure: A film reel contains a long, flexible strip of plastic film. This film has a thin coating called an emulsion on one side.
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Light-Sensitive Emulsion: The emulsion contains millions of tiny silver halide crystals. These crystals are sensitive to light.
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Exposure to Light: During filming, the camera lens focuses light onto the film strip. When light strikes the silver halide crystals, a chemical reaction occurs, changing the crystals. The stronger the light, the greater the change. This essentially imprints a latent image onto the film. When those crystals are exposed to light through the lens, the emulsion darkens the pattern of the image being captured.
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Developing Process: The exposed film is then processed in a darkroom using chemicals. This developing process amplifies the changes in the silver halide crystals, making the latent image visible. Unexposed crystals are removed, leaving behind a stable image. The areas that received more light appear darker, and areas that received less light appear lighter, creating a negative image.
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Projection (If Applicable): To view the film, it's often projected onto a screen. A projector shines a bright light through the film, and a lens system magnifies the image onto a viewing surface.
In summary, film reels rely on the light-sensitive properties of silver halide crystals to capture images, which are then developed and often projected for viewing.
