Wider really is better...

After I purchased a Canon EOS 3 body, I found that it would only use the fancy AF mechanisms with f/2.8 lenses (like the EOS 1n). If this was a scam on the part of Canon to get more people to by L lenses, it worked on me!

CONSTRUCTION

The construction of this lens is beautiful. The body is a combination of metal and polycarbonate. It exudes a feeling of solidity. Both the zoom ring (at the rear) and the focus ring (at the front) are silky smooth with a nicely damped feel. The AF/MF switch is just behind the focus ring and is easy to reach while handholding the camera. This is in contrast to the medium grade Canon USM lenses (gold rings instead of red) which have the AF/MF switch at the rear.

This lens is slightly heavier than the 20-35/3.5-4.5 I replaced it with. However, it is not so much heavier that I felt I needed to keep the 20-35 for lightweight trips.

AF PERFORMANCE

Fast. Really fast. Really really fast. It is noticeably better than the 20-35 (which was a pretty quick to focus lens itself). The f/2.8 lenses really do make a difference on the more costly Canon bodies since they enable the use of the high precision AF sensors. These sensors focus to an accuracy of 1/3 of the maximum aperture DOF and are present on the 1n, 1v and 3. This should result in a higher proportion of keepers.

OPTICAL PERFORMANCE

This lens is sharp. There is some barrel distortion at 17mm, but beyond that there is really nothing I can complain about. Since I typically don't shoot stuff which reveals barrel or pincushion distortion this doesn't bother me. Sure a prime would be better, but a good zoom is so convienent to use that I don't think I should deprive myself. No hairshirts here -- I lived through the no zoom era and all I can say is nein danke.

The 17mm very wide end is difficult to work with. I'll need to refine my technique before I can really make use of it. Prior to getting this lens I had the 20mm focal length pretty well nailed, but the 17 introduces much more perspective distortion. It will take some experimenting before I get the hang of how to use it really well.

OVERALL

If you are a rich stock option kiddie or if you are a pro or aspiring pro, this is an excellent lens. If you only want to spend 1/3 of the amount that this lens costs, the Canon 20-35/3.5-4.5 is a really nice wide angle zoom which is completely capable of producing professional quality shots.