If you’ve ever read any advice on choosing paint colours, no doubt you’ve come across the idea of warm colours and cool colours, as well as warm or cool light. As a rule of thumb in the northern hemisphere, rooms with south-facing windows receive a warm (yellowy) light which shifts as the sun moves across the sky, creating strong contrast between sunny and shadowed parts of the room. Rooms with north-facing windows have a consistent cool (blue) light throughout the day. Rooms with east-facing windows receive warm light in the morning and cool light the rest of the day, whilst…