I love sheila's pictures here but I honestly do not see any reason in those pics to say oh yeah I got to get the 17-40L?
At the small size they are being shown and with similar processing to obtain a good result I want to make a bet nobody will be able to see the difference between both lenses.
If this is supposed to be the results you want I would rather say get the 17-85 it will give you more opportunities to take the pictures you want then the 17-40.
For what it is worth I don't have the 17-85, but do have the 17-40 and find it a very good lens at f4 and great at f5.6 and above. From what I have seen in these reviews the 17-40 is optically better, but that should be no surprise as it has a smaller zoom range, was designed for full frame cameras and of course it is an L lens. That said the difference doesn't seem to be huge.
I do plan to add a 17-85 because it is the only lens that covers the 28-135 35mm equivalent that is so convenient and it has IS which is very useful. For times when I don't want to fuss with changing lenses this seems ideal. The IS and zoom range combined with the high ISO capabilities of cameras like my 20D open up a whole new range of possibilities. A small loss of optical quality compared to Canons best L lenses seems like a fair trade off to me.
here is a handheld shot with the 17-40 at f8. I had the 17-85 for about two weeks and returned it. It just was not as sharp as my 17-40 in any light conditions. not to mention the build quality is far superior on the 17-40. Most camera stores offer a 2-4 week return window. or you can do some in store test's, so go test them for yourself.
Having used a 17-85 IS on a 20D for both personal and professional use and a 16-35 f:2.8 L on both my 20D and 1D (Mark I), I ended up liking and using both lenses. The 17-85 is lower contrast, plenty sharp between f: 4 - 8, but has somewhat soft extreme corners in the 17-25mm wide range, whether or not stopped down. However, when the light gets lower the IS gives me less camera shake -- subject motion blurr can then sometimes be a problem. At least for me, when shooting something where the wide angle edges and L lens contrast aren't a concern, then the 17-85 IS lens is a more versatile choice.
they are a mobile that an old fisherman made out of un-furled Crabbing ropes. he had them hanging from a branch over the beach. here is a picure with the branch, I just thought it looked cool with them floating in the air like flying jellyfish
