Computer Programs

Available computer programs accurately design lighting systems using photometric curves and data for various fixtures. Some programs allow the user to input items such as trees and other physical barriers that may interfere with the output from the light fixtures. These programs will calculate luminance, illuminance, and glare. Dirt and maintenance factors that depend on the environment of the fixture location and the type of fixture are also used in the calculations. Some of the programs are easy to operate and very user friendly whereas some require much more detail. Computer-generated drawing files can be imported into the program, thus allowing the use of available site and roadway plans without the necessity of compiling a new drawing. Lighting manufacturers have made photometric data available from their company websites, and this information can be imported into the software program. After the design is completed, some programs are capable of providing a three-dimensional rendering showing a pictorial view of the pro­posed area. With the ease of obtaining all required input information, a lighting designer can experiment with the use of various fixture styles, wattages, and photometric patterns. Thus, the designer can obtain maximum light levels with consideration of both initial installation costs and annual operating costs, which include energy costs and maintenance items such as cleaning and lamp and ballast replacement.