When I
first decided I wanted to have a "Ultra" wide lens, I was very misguided. I thought, I would find a lens that allowed me to make dramatic pictures out of beautiful landscapes and far off objects by encompassing more in the frame. What I got where tiny
caricature of once grand wonders. My first ultra wide was the
Canon EOS EF-S 10-22mm f/3.5-4.5. I was a nice lens, don't get me wrong. It is even faster at the wide end than my current
Canon EOS EF 17-40mm f/4 L. I just didn't use it properly, and when I got a chance to sell it for a profit*, it was gone.
The problem wasn't my method, simply my application. Today when I want a striking landscape shot, I wait for it with either my 50mm f/1.4 or my 70-200mm f/2.8 IS and pick out the best subject from what is before me. When I want to exaggerate the heck out of something, I grab an ultra wide. Be it architectural, nature or even sometimes portrait photography, an ultra wide can have great uses, mainly to distort in some way. At a friend's wedding a while back I had to step in and be the substitute photographer because the one they hired was late, and less than skilled. I didn't have much equipment other than the 10-22 and a niftey fifty with me so it was a challenge, but here are some examples of what I did well and not so well with the 10-22.
First the poorly done.

Most of this picture is wasted space.

Other than the obvious faults in framing and composition, I mananged to make everyone look unnatural and the gentlemen at the egdes have been streched to unflattering purportions.
The slightly better.

Other than a face being obscurred, this picture came out much better. The guys look as though they have wide shoulders and nearly tower over you. They also appear much larger in comparison to their surroundings. The distrotion in this case doesn't detract, but rather enhances the desired effect. I wish I had understood this lens better. In hindsight I could have done some fun things with it at this wedding.
Weddings aren't really the best place to use a tool like this. The opertunities are few and if it is overused it becomes quite stale. This isn't to say it can't be used to go effect.

The young man on the right was the wild man of this wedding. Nothing but an ultra wide could have captured the mood that you see here.

Here is another that I really liked from the same wedding.
I think my flavor of the week subject material, when it comes to my 17-40mm, are equipment and cars. I can't get enough of the sense of size that the lens can produce.





In short, ultra wide angle lenses aren't at all what a lot of people expect them to be. Once you understand them, you realize what you were missing.
*I bought this lens used for $450 and sold with the hood I bought for an additional $45 for a sum of $600. All in all, it couldn't have worked out better for me.