Andymcbratlie asked a question:

This is totally OT, but what do you think of Sigma lenses? I work at a rather large electronics retailer here in Norway, and we sell both Tamron and Sigma, since I'm in the brown goods department I don't really know much about lenses and stuff, but the customers keep asking me about them. Both Sigma and Tamron are in the lower price range, so I'm wondering if they are good value for the money

What do you think? What are your opinions of other 3rd-party lens manufacturers?

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