A Novel Method to Prove the Visibility Distance of Candlelight and the Milky Way’s Vega Star and Apply this Knowledge to Outdoor Lighting Applications

Understanding the human visual system’s night-time performance is essential for designing safe lighting for night-time travel. Visibility is a complex assessment process, but our current understanding of how the eye receives and processes light and how well the eye can distinguish objects in different lighting levels and distances are low. The current approach for calculating outdoor lighting level requirements is complicated and limited to illuminance and luminance measurements and does not allow designers to evaluate visibility. This paper aims to develop a simple outdoor lighting visibility calculation using the photons per second. This novel calculation method is applied to the candlelight's visibility distance and the milky way’s Vega star visibility to validate the calculation approach. This paper will help researchers, scientists, engineers, consultants, architects, lighting designers, and government agencies seeking to improve outdoor lighting for safety, health, well-being, and quality of life in the built environment.