The 17-40mm f/4L is a very solid performer and a very good value at $680.
It's not as good as the more expensive 16-35mm f/2.8L ($1370) in terms of sharpness, colors(!), and auto-focus reliability. The 17-40mm is also somewhat soft on the 17mm end. However, it has one advantage: the extra 5mm of length come in handy more than you'd think.
I tried 2 copies of the 17-40 and 2 copies of the 16-35 as well as numerous other wide angles. I ultimately ended up with the 5D and the excellent 35mm f/1.4L (35mm is like 22mm on a 20D) and have never looked back.
I've read that the 17-40 does better on a full-frame body such as the 5D. Perhaps this is due to the lower pixel density. I'm holding out for Canon to create an excellent prime in the 20mm range.
On a 1.6x crop body, I'd probably get the new EF-S 17-55mm f/2.8 IS because it is supposedly very sharp and because it has more reach and IS. I never had a chance to try it while I still had the 20D.
I recommend the The-Digital-Picture.com for comprehensive reviews.
It's not as good as the more expensive 16-35mm f/2.8L ($1370) in terms of sharpness, colors(!), and auto-focus reliability. The 17-40mm is also somewhat soft on the 17mm end. However, it has one advantage: the extra 5mm of length come in handy more than you'd think.
I tried 2 copies of the 17-40 and 2 copies of the 16-35 as well as numerous other wide angles. I ultimately ended up with the 5D and the excellent 35mm f/1.4L (35mm is like 22mm on a 20D) and have never looked back.
I've read that the 17-40 does better on a full-frame body such as the 5D. Perhaps this is due to the lower pixel density. I'm holding out for Canon to create an excellent prime in the 20mm range.
On a 1.6x crop body, I'd probably get the new EF-S 17-55mm f/2.8 IS because it is supposedly very sharp and because it has more reach and IS. I never had a chance to try it while I still had the 20D.
I recommend the The-Digital-Picture.com for comprehensive reviews.
