I taught at the Photographic and Imaging Show in Mississauga today and met many interesting people. I wrote four “choosing the right lens” workshops, which I teach there all weekend.
So on that theme: what is the lens I should use for a trade show?
While I usually shoot with flash, at a show like this of course natural light is often a better option. So I want fast lenses.
800 ISO is fine, with a modern camera. And that is enough for 1/500th second at f/1.2 with a super-fast 50mm prime lens. On a 1.3 crop camera, this gives us an effective 65mm:
This type of slightly longer than standard lens focal length gives us slightly compressed perspective while still retaining a natural look.
If instead you want a more dramatic three-dimensional perspective, use a wide lens. A 16mm zoom set to 16mm (meaning, on this camera, a 35mm equivalent of 20mm), gives us this:
(This was also 800 ISO, but now 1/60th sec at f/4 – meaning an equivalent exposure, just shifted up)
Both images were, as you see, tilted to compose well, and to simplify.
So if I had to give you a quick answer, I would say: “wide or standard, and above all, fast, like f/2.8 or faster”.