Lighting Design

Surfaces and objects in a space may be considered an extension of the lighting system. If light is not absorbed, it is reflected and transmitted with reduced intensity to other surfaces and objects, where it is absorbed, reflected and transmitted. All surfaces and objects in a space that reflect or transmit light can be considered [...]

This coefficient of utilization table is published for a given indirect general lighting product considered for installation in a room with a 20 percent floor reflectance, 30 percent ceiling reflectance and 50 percent wall reflectance. The room cavity, defined as the volume of space between the luminaires and the workplane, is 5 ft. high x [...]

Electrical Contractor Magazine recently published an article I wrote about how to read a luminaire photometric report, part 2 in a short 2-part series on lighting design basics. The article includes how photometric measurements are taken, what kind of useful outputs are generated, and how to read and interpret those outputs. Check it out here. [...]

From a recent email from the International Association of Lighting Designers (IALD): Please be advised that the State of New York has determined that the lighting design services that our members typically provide to customers are subject to sales tax in New York. The Department’s conclusion applies to ANY lighting design firm providing services in [...]

Norwegian researchers have found that good design and lighting can significantly reduce anxiety among travelers driving through tunnels, as reported by EarthSky.org here. The article states: The main point is to obtain a good distribution of light, in conjunction with the use of artistic lighting, which turns out to give drivers a feeling of space [...]

For those specifying color characteristics of light sources, a few words of caution: While color temperature and CRI are important, the true complexities of a light source’s color characteristics cannot be captured with a few numbers, which is why there is no substitute for seeing the lamps in a given application. A separate mockup with [...]

Light is actually made up of colors. For an object to be perceived a certain color, that color must be present both in the object and the light striking it. Because of this, choice of lamp can influence how colors are perceived in a space. This means that perception of objects in the space is, [...]

Excessive luminances or luminance contrasts may also lead to a visual sensation called glare, which, even though it is also light, can impair or disable vision rather than enable it. Glare is categorized as several different types according to its effects. Direct glare is caused by directly viewing a light source, such as a bright [...]

Specifying color quality appropriate for the application is essential. In a high-end retail application, good color quality can make products, especially clothing, appear more vibrant, truer and ultimately more appealing. In an office application, color quality can facilitate social interaction by rendering faces more naturally and thereby helping to create a more productive and appealing [...]