It is a good decision to change halogen or fluorescent lights (either tubes or CFL) to LED lights. The cost and the payback period can be as little as 12 months, (check out the calculator), and you have more choices for lighting and luminaires. What are the choices for “colour” and brightness, without getting into technical terms such as Lumen and Lux. It is important to understand that these terms are relevant rather than the old fashioned “wattage” which really only told you how much electricity went into the light. Not how much you get out!
What is Colour
With LED technology, the light actually comes from an electrical process at the molecular level. Because of this, the energy of the light that comes from and LED light can have different energy levels; and our eyes see this variation as colour. Initially, the first LEDs were red and green, and it is only in the past 5 years that the blue LED has been available. LED colour is a mix of these primary LED emitters. In the diagram, different energy (temperature) provides different colour. The bluest is at 8,000oK (degrees Kelvin temperature) and the reddish is at 2000oK . Which light is best? It depends. A warm white light is suitable for a living room, but a cool white is suitable for a kitchen or bathroom (or dental clinic). Daylight is normally about 5000k. Remember this is not the same as the light spectrum which ranges from light wave lengths from about 400 to 800nm.
What does this LED range look like with different colours?
Digilight recommends natural white. Cool is quite stark, and sometimes even blue. Compared with incandescent or halogen lights that tend to be “warm” white, or cold harsh light from fluorescence tubes or compact fluorescence lights. Natural White LEDs are about about 4,500K up to 6,000K the same as early morning / late afternoon. Good manufacturers will have very consistent colours, but other manufacturers tend to have variation. It is important to purchase by batch, or there may be some noticeable variation in colour.
Colour results from the balance of visible light emission
The LED colour is the resultant mix of three primary LED emissions Red LEDs, Green LEDs and Blue LEDs. With a Cool White LED colour, there is more blue LED to provide the bluer colour. With a Warm White LED, there is less blue, and more Red LED.