A reducer is a chemical solution used in photographic processing to decrease the density of a developed negative or print. Often referred to as Farmers Reducer, it works by removing or lightening silver from the emulsion, allowing photographers to correct overexposed or overly dense areas.
Reducers are commonly used in darkroom photography for precise control over contrast and tonal range, enabling adjustments without re-photographing the original subject. They are an essential tool for fine-tuning negatives to achieve optimal exposure and print quality.