We had to rely on lighting consultants and manufacturers for design philosophies, standards, guidelines and performance characteristics of a wide range of applications and products. Our Committee efforts were divided into administrative or programmatic work and the compilation of technical information on practical lighting systems for roadways and pedestrian paths. We recommend luminaires that may differ from what others advocated for light pollution abatement. As amateur stargazers, most of us have experience with all three.
Glare is caused by light that is emitted close to the horizontal direction.
Such horizontal light can be seen for many kilometres and reduces our dark adaptation. Lighting professionals are well aware of how glare can reduce the personal safety of both motorists and pedestrians by reducing the visibility of hazards. Glare can be quantified by relating the luminance of a light source to the illumination of a surface. The angle between the illuminated surface and the light source is also a factor. The brighter the light, the lower the reflectivity of a surface, and the closer the light is to our centre of vision, the greater the level of glare.