What is an IES profile in lighting?

The IES file format is named after the Illuminating Engineering Society. The group brings together lighting experts to better design real-world lighting conditions. IES is also the technical term for photometric plain text files that contain light data for architectural programs that can simulate light.

Lighting manufacturers may publish files in this format to describe how various structures are affected by their products. Programs that use this file can interpret it to understand how to display the correct lighting patterns on objects such as roads and buildings.

A simple text editor can also open IES files, since they are just plain text. However, doing so will not allow you to see any visual representation of the material, only the textual content.

The free DIALux program can open ULD files, i.e. Unified Lighting Data Files. You may be able to import an IES file into the program and save it as a ULD file.

IES ultimately influenced the development of various standards for certain lighting applications, such as those used in medical facilities, sports environments, offices, and more.