It is important to validate the contents of an IES file to ensure the integrity of downstream calculations, such as lighting designs.
Files conforming to the IES-NA LM-63 standard are one example of a photometric data file. The IES files are text based and encapsulate descriptive and physical data of a photometric sample. The typical end user of an IES file is a design engineer who will use the file in lighting design software to simulate the performance of a sample in an installation.
An IES file is typically generated by one of two processes: by a laboratory on a real sample or by simulation software. The file is then distributed, through possibly several layers of intermediaries, to the end user. Because the IES file is stored in plain text it is possible for the contents to be modified without the knowledge of downstream users. This diminishes trust in the IES file as a means of distributing data.
LightLab is a photometric laboratory with an interest in maintaining trust in the IES files that it publishes. In the document below, methods are discussed to validate IES files against trusted sources.