The Colour of Light

When it comes to LED lighting for the home, most people profess that they “don’t like that type of “cold”, blue light you get from LEDs”. They prefer a “warmer” light as it provides a “warmer” atmosphere, more appropriate for the home.

It’s funny because after 2 years of testing, comparing and running a range of LED lights both at home and at work, my partner and I have come to the conclusion that, compared with pure white LEDs, halogen and incandescent lighting appears “dirty” and “yellow”. Anyone notice the connection between colour and emotion?

Compared with the alternatives – halogens, fluoro tubes and CFLs, our pure white LEDs are easier to work under, computer eye strain is reduced and because these lights mimic natural, middle-of-the-day Australian spring sunlight, we are able to forget that we’re inside for 8 hours of the day. In fact, we feel that we could never again tolerate “warm” light on a 9 to 5 basis.

LED lights come in every colour of the rainbow. They’ve been used for decades in cars, boats and aeroplanes and for airport and shipping lighting. You can even get warm LEDs if you really want them. It’s a matter of selecting your preferred “colour temperature”, the standard unit for measuring the colour of light, as expressed in Kelvins (K).

Temperature Range for LEDs

Colour interpretation can vary from person to person and is influenced by experience and even emotion. The human eye cannot detect changes in brightness or colour temperature of less than 30%.

The colour description which we give to our LED lights refers to the following ranges:

* 4500K-5500K (Warm White)
* 5500K-6200K (Pure White)
* 6200K-7500K (Cool White)
* 7500K-10000K (Cold)

Incandescent and halogen lights tend to have a colour temperature of 3500 to 4500K, resulting in a yellowish light. (Incandescents can appear more white when their wattage is very high. Dimmers are used to turn incandescent high wattage light bulbs - 75 to 100W – from bright white light to warm light – while still drawing the same power).

Fluorescent tubes are mostly seen in supermarkets and commercial settings as cool to cold white but are also available as warm. Compact fluorescent lights (CFLs) are used mainly in restaurants and homes and are mostly available in warm colour temperatures.

White LEDs start at around 4500K and can be produced as high as 10000K. After 6500K, lights tend to appear cooler and brighter. Most commercial lighting is configured at around 7500 to 10000K. These lights can have slight blue tones to them and tend to be very bright.

Full Spectrum Lighting

When you strike the right balance of lumen colour rendering index (CRI) and colour temperature, you get light which mimics natural sunlight and is described as full spectrum lighting. Full spectrum light is believed to improve mood, work efficiency and help to reduce glare and eye fatigue. Natural sunlight helps to keep the stress hormone, cortisol in check and balances melatonin levels. People who work inside all day without full spectrum light or natural light are more likely to suffer from depression and insomnia.

Which white light is right for you?

We recommend pure white light for most applications in the home and at work. Cool to cold LED lighting is necessary for commercial situations where Australian standards apply. Yes, LEDs do produce a different type of light to that coming from halogens, incandescents and fluorescents but it won’t take long before you find them to be far superior to any other artificial light source. You won’t look back.