ETC has seen deposits of white material that looks like dust or flocking on Source Four fixtures, generally on the yoke and c-clamp, but is has been observed inside of the fixture body as well.
It seems to occur most often when fixtures are:
- Lamped at high wattage
- On for long periods of time, such as in worklight applications
- Pointed straight down
- Used with saturated dichroic filters that reflect heat back into the fixture
The white substance comes from the polyester-based powder coating on our fixtures. We have had this material analyzed by two different third-party labs. Both labs have reached the same conclusion: that in the very low concentrations produced in this situation, the material is not harmful or dangerous.
The substance can easily be cleaned off by allowing the fixture to cool, then wiping it with a dry shop rag or other suitable cloth.