At what point does longer focal length no longer matter? I want to take photos of things far away, like across the street.

I would do a camera test if I still owned my 70-300 Canon kit lens but I don’t. Right now the longest focal length I own is a 24-70 for my Sony.

I remember about that lens, once I got out past 150-175m, it seemed like the FOV was just cropping in more rather than actually feeling closer to the subject. But that was a cheapo kit lens that had a terrible reputation. Does that just apply to cheap lenses or do more expensive lenses have more magnification?

Is there really a significant difference between 300, 400 and 600m lenses? Of course I have no physical access to any such lenses at the moment.

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