Light is detected by rods and cones in the retina in our eyes. Rods are more sensitive and we have 120 million of them but they only see light and dark. Cones are used for our colour vision, about 7 million of them, and are clustered in the centre of the retina. Cones work best in bright light and in dim light we use mainly our rods. Looking at the Aurora at nighttime our eyes, using mostly rods, don’t pick up the colours and intensity so the Aurora looks faint. In comparison, a digital camera can process more of the light and results in vibrant images that we don’t see ourselves.