What are MH (Metal Halide) lamps?
Metal Halide lamps are popular because they have a low colour temperature. Generally MH lamps have a colour temperature of 6500Kelvin. This means that they are a cooler running temperature and also emit a blue-white light that is a closer imitation of sunlight then HPS lamps. This closeness to natural sunlight is expressed as a CRI (Colour Rendering Index). The CRI of most MH lamps is in the range of 60-70. This means that they are 60-70% close to natural sunlight. While this CRI is quite high, MH lamps do not have a very high lumen output. As a result they do not last as long as HPS lamps.