Well, back in MY day, we didn't correct for such things :) A wide angle shot should look like a wide angle shot and that means that you see the perspective in it. Personally, I see a lot of talk about this and complaints that certain wide angle lenses have various "distortions". And yet, to me those so-called distortions are often what I find so endearing about shots taken with a very wide angle lens. I have a tilt-and-shift lens (FL so it won't work on my 20D, unfortunately), and you can get some amazing results with such a lens. But to me, a shot like this benefits from the extreme perspective. Maybe it's just us old guys who feel that way. Jim H.
