Distribution photometry is performed on lamps and luminaries to produce IES files. IES files are electronic files which contain the data that represents both the distribution (intensity in candelas at combinations of lateral and vertical angles) and amount of light being emitted (lumens) from either lamps (light bulbs) or luminaires (light fixtures). Architects, engineers, lighting designers and others import these IES files into their lighting design software. With the lighting design software, they can produce lighting layouts that accurately predict and show (on architectural drawings or 3-D renderings) light levels for both indoor and outdoor applications.  


Standard ITL Roadway Report includes:
  • Candela Tabulation
  • Polar Candela Traces of Maximum Plane and Cone
  • Lumen Summary, House and Street Side
  • BUG ratings
  • Total Efficiency or Efficacy
  • Coefficient of Utilization Curves
  • Photograph showing Luminaire Dimensions
  • Isoilluminance Contour Plot (fc or lux)
  • IES File
  • Test Report in PDF format
Possible Adders/Options (Applicable to Indoor Photometry)
  • Additional Iso Contour Plots
  • Each additional lamp beyond the first for luminaires with multiple lamps operating
  • Low Pressure Sodium lamps
  • Candela tabulation at other than 22 1/2-degrees lateral by 2 1/2deg. vertical steps (for luminaires with very narrow distributions and testing at other than standard IES increments)
  • Testing angles that require extraordinary aiming/setup time and/or odd angle sets requiring additional testing time.
  • Flux measured in two hemispheres requiring a second setup in order to gather data in upper and lower hemispheres, unobstructed by the goniophotometer. One setup can usually gather light up to approximately 160-degrees vertically from the primary direction (up or down). Testing that has light directly up and directly down will usually require this additional setup.
  • Prorate to other lamps/lumens
  • Hazardous lamps (Ozone,UV, etc.)