Pros: Compact fluorescent lamps are super energy efficient – they produce a quarter of the heat per lumen of an incandescent light bulb and last about six times longer (about 6000 hours). Cons: To the conventional eye, fluorescents sometimes seem too bright and appear to make colours look unnatural and garish. To combat this, opt for the yellow-tubed fluorescents (such as ‘warm white’) instead of pure white ones, or an extremely low wattage lamp.Also, fluorescent light cannot be used in dimmers. Light-emitting diodes (LED).This is expected to be the most practical light source in the years to come. Generated by a semi-conductor, it’s the light you see in flashlights and cell phones. Pros: LEDs are five times as power-efficient as fluorescent lighting but there is a catch – at present, the microchip inside the LED light only emits light in one direction. It doesn’t reflect it back, which means it doesn’t allow us to see colour. The solution is to design lenses that go on top of the LED and disperse the light. When light tricks our sight Most of us will have experienced the navy sock/black sock scenario. You take a pair of apparently black socks out of the drawer, then realise later that one of them is actually blue. Don’t worry, it doesn’t mean you’re colour blind – it’s a common phenomenon called sample metamerism. The reason for the optical illusion is that the wavelength emission between various light sources, such as incandescent and fluorescent light, differs. Incandescent light bulbs emit very few short blue wavelengths, which makes it hard to tell whether a colour we see in such light is dark blue or black. Fluorescent light, on the other hand, emits more short- wavelength light, and so it’s easier to distinguish the two colours. On the flipside, you can also have two identical colour samples that look vastly different when viewed under different lights. This phenomenon, called illuminant metamerism, explains how retailers (or homeowners) can use light to present their product (or your interiors) in the most flattering light. There are various other ‘metamerisms’. One is observer metamerism – the fact that individuals perceive colour slightly differently. Another is geometric metamerism – the different appearance of colours when seen from different angles, distances and light positions. Did you know that one reason men and women often see colour differently is that the distance between a woman’s eyes is usually slightly less than a man’s? Metamerism also affects the way we view paint colour charts, which is why Resene uses actual Resene Environmental Choice approved paint on many of its colour charts, such as The Range fandeck series. The next time you have a colour chart and a testpot that you think don’t match, try wandering outdoors – you’ll often find they are a perfect match and it is just the interior lighting that is making them appear different. Wherever possible, it is best to develop a lighting plan at the same time as your paint scheme. For example, if you decide to paint any of the rooms in a dark colour, you are likely to need more lighting than if your walls were pale and would therefore reflect the light. Resene Seachange | 37