GDTF Files - How to open and find Emitter Data for use in ChamSys Head Fixture Profiles

Emitter Data for use in the Head Editor, View Other, can be obtained from GDTF files created by manufacturers.

1. Download the manufacturer's GDTF file from GDTF Share
2. Rename the .gdtf to .zip, extract it, and open description.xml.
3. The section has each emitter's CIE xy in the Color attribute. Ignore the Y value in that attribute (it's normalized to 100 for every emitter), and instead use the **Luminous Intensity value** from the Measurement child element — that's the actual relative output ChamSys needs for color mixing: Luminous Intensity Value = Luminosity in ChamSys.

Important Note: ChamSys uses relative values of Luminosity for the emitters within an individual head in MagicQ to compute the outcome using the ChamSys color picker algorithm. You may notice that some heads have Luminosity values that do not match those found in the GDTF file. Provided the relative values of one emitter to the others are the same in the head profile as those in the GDTF file, then the head profile will be equivalent when used in the ChamSys system.