GDTF files and the PID library

The bench reads two kinds of file it does not get from the fixture. Each one answers a question the fixture cannot answer itself, and neither needs the other:

• GDTF files answer what does a desk call this mode? They are the fixture files a lighting desk loads to patch a fixture. The bench reads only their mode names and channel counts, and uses them to turn the fixture’s personality into the name the desk shows in its patch.
• The PID library answers what is this manufacturer parameter? Its tables put names to the maker’s own parameters, the ones E1.20 does not define, when the fixture lists them but will not describe them. Its fixture profiles record what particular models are known to get wrong, and the channel layouts their manuals give.

Both are found by the same numbers the fixture reports about itself: its manufacturer ID, its model ID and, for GDTF, its firmware. A file for the right brand but another model is never used. Both are read on the bench, with no network, and both work on a saved report as well as a live fixture.

Three kinds of profile

“Profile” means different things depending on who is saying it, and this help keeps them apart:

• A desk profile is what a lighting desk loads to patch a fixture: what each channel does in each of its modes. Every desk has its own name for it: a fixture profile on ETC Eos, a fixture type on grandMA, a personality on Avolites and ChamSys. GDTF is a format meant to work on any desk. The bench reads GDTF files and never writes a desk profile (see Build a desk profile from the fixture).
• A fixture profile, in this help, is the PID library’s record of one model: its modes, its sensors, what it is known to report wrongly, and the channel names its manual gives. An Eos fixture profile is a different thing, the desk profile above.
• A PID is not a profile at all. It is one parameter a fixture can be asked about over RDM, such as its sensors or its mode, defined by the E1.20 standard or by the fixture’s maker.

Personality is ambiguous too: in RDM, and in this help, it means one of a fixture’s modes, not a desk’s file.

How they work together

Take a fixture showing the wrong colors with no error code. The report reads the fixture, then each file fills in what the fixture could not say:

1. The fixture says it is in personality 2, which it calls Standard (16-bit), 25 channels wide. Anything the fixture says about itself always comes first, and nothing in either file replaces it.
2. A GDTF file for the model says personality 2 is the mode the desk calls Standard. If the desk is patched as Extended, that mismatch is the fault: the desk sends one channel layout and the fixture reads another.
3. The PID library names the maker’s own settings in the report’s Parameters list, such as a color calibration or a dimmer curve, so you can see whether one of those was changed instead.
4. A fixture profile, if the model has one, warns of anything the model is known to report wrongly, and names the channels in Send DMX for a fixture that does not name them itself.

With neither file, the report is still complete: the mode is shown by the fixture’s own name and number, and an unnamed parameter by its number in hex.

Where each one comes from

• GDTF files come from the desk’s own fixture library, the GDTF Share, or the maker’s downloads. You add them to the bench’s GDTF folder; nothing fetches them for you without asking. See Find a fixture’s desk mode.
• The PID library comes with the app and keeps itself up to date from the public RDMBench PID library. You can add to it from any fixture that describes its own parameters. See The PID library.