droop

[derekleffew]

1. More specifically, "thermal droop." A phenomenon of LED luminaires whereby since output diminishes as heat increases, fixtures will exhibit less output over time. The look you set in the morning may not be the same at the end of a long day of programming. Higher quality fixtures have compensation to counteract this.

From an ETC/Selador marketing document:

Heat management has been another area of
emphasis in the development of our fixtures, to work on the problem
of ‘droop’ that all LEDs inherently have (the output of light is reduced
as the temperature rises in the LED). So, we worked on solutions to
regulate the fixture better thermally than other LED brands.

2. Droop over time. The luminous output of all LEDs will decrease over time. Although usuable lifespan may be 25,000-50,000 operational hours, most agree that 70% of original qualifies as "end of life." This can be particularly frustrating when adding new fixtures to existing ones, even if the same model.