So what makes the lens so great? Why will it revolutionize architectural photography? Both questions can be addressed with one answer: the lens reduces the post-production (Photoshop) time that is the bulk of digital photography work these days. The combination of full-frame format wide angle (104 degrees) and free combination of tilting and shifting (4mb PDF) means that vertical lines do not converge towards the top of the photo and barrel distortion is eliminated, a la the photograph below. Take a look at just about any professional architectural photographer's portfolio, and, unless the shot is a craning view of a skyscraper, 9 times out of 10 the vertical lines are parallel. This is a lens that makes such results easier.