The lens was an old Canon L 16-35 2.8, a very expensive lens.
I feel a good lens is way more important than most people realize.
For me, the most important thing about a lens isn't how sharp it is, or how much better the distortions may be, or how consistent the exposure is across the frame. I consider how wide the largest lens opening is, and how fast the lens will focus. This Canon 16-35 2.8 zoom lens is a constant 2.8, meaning if I zoom into my shot while wide open with the aperture (2.8) it will stay at 2.8 and not stop down like most zoom lenses. Tamron Tokina and Sigma must offer a similar lens at a better price I think.
Sorry I'm being so nerdy.
Camera model-Canon EOS 40D
Focal length-28 mm
Max lens aperture-f/2.8
Exposure-1/800 at f/2.8
Flash-Not fired, compulsory mode
Exposure- bias0 EV
Exposure mode-Auto
Exposure prog.-Aperture priority
ISO speed-ISO 400
Metering mode-Pattern
Here is the frame right before which I also like