Light bulb colour temperature spectrum. This spectrum shows how the overall hue of the light from light bulbs can vary in terms of a calculated characteristic known as colour temperature. The light produced by a source such as the Sun or a light bulb will include a range of colours, but this can be averaged out to obtain its colour temperature. The range shown here is from 1500 to 8000 Kelvin. Seven examples of light bulbs are indicated: highpressure sodium, standard incandescent, halogen, three types of metal halide, and cool white fluorescent. Daylight is 5500 Kelvin. For this spectrum without the labels or examples, see C0116359.