Purkinje Shift

The chances are as a photographer that you pay close attention to light and colour, even if you don’t have a camera in your hand. It’s possible then that you might have noticed how your colour perception changes as the light fades.

It’s self-evident that we have no colour vision in the dark. You only have to wake up in the night, give your eyes a moment to adjust, and see for yourself.

But have you noticed how anything that’s red, or perhaps yellow or orange, tends to appear more dull as the light fades while anything that’s blue looks more vivid?

That’s because human vision is dependent on rod and cones cells within the retina. Cones are responsible for photopic vision, making them active in well-lit conditions. Rods, on the other hand, are responsible for scotopic vision, or when it’s dark. Cone cells are capable of detecting colour, whereas rods are essentially colour blind but more sensitive to light at the bluer end of the spectrum.