I’ve noticed that in old black-and-white footage of people performing music onstage, when the spotlight hits a reflective part of an instrument, the resulting glare often appears black. What’s up with that? Is there some kind of solarization thing going on?
This sounds to me like a problem with old TV cameras (even if the show was then recorded off a scope onto film). The camera gets oversaturated by the light and you got a black blotch.
That’s probably it – old TV cameras “went blind” for a few seconds if there was too much glare.