Coupled dyes are the visible colours produced during the colour development process in photography. When a colour film or paper is developed, chemical reactions occur between exposed silver halides and specific dye couplers, forming stable coloured compounds. These coupled dyes are responsible for reproducing the reds, greens, and blues of the original scene, creating accurate and vibrant colour images. Understanding coupled dyes is essential for photographers and printmakers working with colour films and papers, as they determine the final hue, saturation, and overall colour fidelity of the image.