Think about color temperature before changing your lights

Upgrading your lighting is now a standard practice with a range of benefits including energy savings and reduced unit costs. Unlike the curlicue CFCs and other traditional filament bulb predecessors, though, LEDs offer myriad variations.

One of the experts in this field is Douglas Schwartz, CEO of Planet Awaken, which does municipal and large-scale lighting installations. In looking to convert my own home to LED lighting, I contacted him for some advice. Our conversation quickly turned away from unit cost or specific manufacturer and onto optimal color temperature, so much so that I arranged for a formal interview so that I could convey his full thoughts on one prominent side effect of LED conversions. 

According to Schwartz, there are two key parameters when addressing lighting color: temperature and accuracy.

Color temperature is a method of describing the hue characteristics of light, usually either warm (yellowish) or cool (bluish), and measured in degrees of Kelvin (°K) as a low burning fire would give way to oranges, yellows and all the way up to white hot. Here is what a room looks like with lighting at different degrees of Kelvin.

Upper left: A room lit at 2000K; upper right: at 3000K; lower left: at 4000K; and lower right: 5000K
Upper left: A room lit at 2000K; upper right: at 3000K; lower left: at 4000K; and lower right: 5000K

Despite these differences in color temperature, not all artificial light sources are equal in their accuracy, either. The Color Rendering Index (CRI) measures the ability of a light source to accurately render all frequencies of its color spectrum, when compared to a perfect reference light of a similar type (color temperature).

This is rated on a scale from 1 to 100. The lower the CRI rating, the less accurately colors will be reproduced. For reference, an incandescent bulb is a perfect 100.

Not to confuse you, the CRI comprises 14 unique scales: the first eight (R1 – R8) are for medium saturated colors and the last six (R9 – R14) pertain to highly saturated colors (red, yellow, green and blue) as well as complexion and leaf green. Below are two examples to show how CRI results affect the way we see objects. I’ve selected food, where appealing to one’s appetite is particularly important.

When planning your LED conversion, as demonstrated above, there is more to consider than just long-term savings. First, select the color temperature, and then carefully analyze the CRI data on your product selection. Ask your supplier for the complete details of each and every type of light being selected.

Make sure that you have chosen the right bulb to meet your guest needs as color temperature can play a profound role in ambient room mood and the impression your hotel makes on visitors. And now that you are appropriately armed with more information on color temperature and accuracy, know that both measurements are only two of the many criteria involved in your move to LED lighting.