Fog level refers to the density that develops in unexposed areas of photographic film or paper during processing. It represents unwanted background exposure or chemical effect that can reduce contrast and overall image clarity.
High fog levels can occur due to aging film, light leaks, excessive development, or contamination of chemicals. Controlling fog level is essential for achieving clean, high-contrast images, and careful handling of materials, proper storage, and accurate processing techniques help minimise this effect, ensuring professional-quality results in both film and darkroom photography.