Relates to how interior space feels. For example, a color temperature of 3000K appears to be warm while 4100K appears to be cool. Color temperature can play an integral part in creating a given atmosphere for a space, whether it be soft and comfortable for relaxing at home or sharp and precise for work environments where visual clarity is a must. One lumen falling on a surface of one square foot produces one footcandle. Glare Glare is any unwanted light that causes discomfort, interference with vision, or eye fatigue.
Direct glare is caused by light coming directly to the eye from a source or bright surface.
Discomfort or reflected glare is light reflected from a surface in the direction of the eye. Illuminance Illuminance is the density of light falling on a surface. It is expressed in footcandles or lux. Lumen depreciation is a term that describes the normal attrition of light. Essentially, the longer a lamp operates, the less light it delivers.