Okay, not everyone hates the Canon RF 70-200mm f/2.8. That's a wee bit of an exaggeration. But more often than not, when I'm using this lens or it comes up in conversation, photographers will say something like, "Oh, that lens?"
They're referring to the love-it-or-loathe-it signature of the Canon RF 70-200mm f/2.8 lens: the telescopic zoom design.
