Reading about the Flourescent fixtures being black reminded me of an instance at work maybe 15 years ago. A project I was on at work involved a line of LED indicator lights in a reflective housing. We went through a large number of iterations for the reflector, first settling on the best shape, which was the easiest part, then went through all kinds of gymnastics trying to get a good reflective surface to project the most light through legend filters and a smoked plastic sheild. Tried all kinds of white surface coatings, silvered coatings, whatever we could find. One day, the boss brought a new concept to me and had me do some light level measurements. Turns out after all the things we tried, the best thing was the plaine, undyed, uncoated black plastic. Not only did it do the best job of reflecting the available light, it cost less than 1/2 what any other approach did.