The term natural lighting is one that is thrown around quite loosely these days in the lighting industry. Very simply put, a lighting source that closely replicates natural sunlight can be considered a natural light source. Sunlight in its pure form has a kelvin temperature of around 5,000 degrees kelvin and a color rendering index of 100. As sunlight comes into contact with the earth's atmosphere and is reflected and refracted by water and dust particles the color temperature actually changes throughout the day ranging anywhere from 5,000 to 6,000 kelvin depending on the time of day and the amount of clouds in the sky. Artificial lighting sources within this range can appropriately be considered a natural lighting lamp as long as the color rendering index is above 90. The color rendering index or CRI is a method for describing the effect of a light source on the color appearance of objects, compared to a reference source of the same color temperature. It serves as a quality distinction between light sources emitting light of the same color. The higher the CRI of lamps with color temperatures of 5,000-6,000 the better objects appear compared to outdoors.
Unfortunately in todays competitive marketplace some companies have taken to making up their own definitions of what natural lighting is. A lamp with a color temperature of 6,500 kelvin and a CRI of 82-84 is simply not a natural lighting source. Even those touting their 5,000 kelvin bulbs with a CRI of only 82 as a form of natural light are doing the consumer a disservice in our opinion. Because CRI is determined in comparison to a source of the same color temperature a company calling its 4100 kelvin lamps a natural lighting source with a high CRI is unequivocally misleading, because the color of the light is actually several shades more yellow than sunlight and bears little resemblance to it. An incandescent bulb with its color temperature of 2800 kelvin has a CRI of 100 and we all know how unnatural those are and the same can be said for these 4100 kelvin halogen lamps.
BlueMax Lighting™ was specifically designed to be the most natural lighting source on the market. The addition of 5 custom phosphors along with a high output 70 watt full spectrum bulb have combined to create the closest thing to sunlight indoors. Having a color temperature of 5,900 kelvin and a CRI of 96+ there are no other lamps on the marketplace to even compare against.