IES files describe how light from a lamp is distributed in a room. This data is provided by many manufacturers so that lighting designers can realistically simulate how a project will look when a specific light source is used.
3D artists also use this data to calculate their images more realistically. However, it is cumbersome to find the correct file using try and error, as the manufacturer does not necessarily include a visual example.
For this reason this page was created. We have enriched existing IES collections with manufacturer data and have reached almost 200'000 data in the end. Using python we read the data, hashed the content as MD5 and assigned the data to the individual manufacturers. Thereby we eliminated duplicates. After this process, there was "only" 160'000 data left.
After that we created a scene in Blender, where a light source hangs 5cm in front of a wall and 1m above the floor. We then calculated this scene automatically for each IES file using python.
The goal was that the preview images should have more or less the same brightness. Therefore we first had to calculate a preview and measure the maximum brightness, adjust the light intensity and finally calculate the image. During this process, data that are too dark are filtered out (luminous intensity = infinity)
Our computer can process approximately 7200 files in a day. These are automatically loaded onto this page and read into the database via cron. It took about 3 weeks to render the first 160k files ...
If the manufacturer provides LDT (Eulumdat) instead of IES, then the data has been converted and both data types are available for download (some manufacturers offer both data types, both files are also provided here).
In the meantime we have added tagging and logging options, after logging in, data can be favored.
So far we have imported every openly available IES file from most manufacturers and achieved 250k entries. We haven't found any new resources to import, so the data collection is complete.
The awesome Blender plug-in "Lily Surface Scraper" can import light sources from the IES library since version 1.6.0. For this purpose, an API has been implemented with which the information can be read into Blender directly from ieslibrary.com.