Colour weight refers to the perceived visual heaviness or dominance of fully saturated colours in an image. Some colours, even at the same intensity, appear darker or more visually dominant than others, affecting how the viewer perceives balance and composition. In photography, a colour's visual weight may differ from how it appears on film or a digital sensor, influencing framing, lighting choices, and post-processing adjustments. Understanding colour weight helps photographers control emphasis, guide the viewer's eye, and create harmonious or dramatic compositions.