Roger Cicala: the difference between sample variation and a 'bad copy' (Part 1)

We fix a lot of lenses, but not all lenses can be fixed. With the next two posts, I hope to end the seventh most common forum war; the 'lens variation is a big problem!' vs 'I don’t believe it exists!' argument. Like a lot of forum wars, it comes down to semantics: Variation and bad copies aren’t the same thing (actually they're not really related at all), but people tend to use the terms interchangeably. Even $2,000 lenses must have variation Note that I said ‘must’. I didn’t say...