> Articles describing this seems to say it's caused by the film medium, rather than being an optical effect. Yeah, I noticed that. Searching the term directly

> Articles describing this seems to say it's caused by the film medium, rather than being an optical effect. Yeah, I noticed that. Searching the term directly gave me results related to film, but when I used other terms describing the effect they mentioned it in a different context. Makes me wonder if someone is just confused.