Just curious, but did you actually test both the lenses you are referring to? Only I did and still went with the 10 - 22. The image quality was certainly comparable (in fact, from what I can recall, the majority of people actually preferred the quality of the 10 - 22 over the 17 - 40, there was certainly not very much in it).

Grey

Possibly the quality between the 10-20mm and the 17-40mm lens may not be the whole story.
I bought the Nikon 12-24mm lens purely for the wide angle aspect same as the 10-20mm you quote , whereas 17-40mm possibly would be better portraits and close telephoto work even though there is an overlap.

Bazza

True, it took me a while to decide between the two (do I go for an entry level L lens simply because it is an 'L' or do I go for the slightly more expensive EF-S lens which, whilst not having the denotion of 'L', takes comparable photo's and allows me to get wide angle shots on the body I currently have). It has been almost a year since I got it and although I don't use it often, I am still pleased with the choice I made. I could have bought the 17 - 40 as I was contemplating going full frame at some point, but looking at the type of photography I mostly do, full frame isn't the best option.

Nope, I had a Canon spec book from Canon, I will see if I still have it. It shows lens performance specs in graphical format for all their lenses. Some of the leses that came out best were the 50mm F1.2 and 85mm F1.2 (best used at F2.0 apparently) and the 100-400 F4-F5.6. Another of the top scorers was the 17-40 F4.0, which at F4 outperforms it's replacement the 16-35 F2.8 (although obviously the F4 can't do F2.8 so can not be compared at that aperture) I didn't buy the 10-22 for the aforementioned reasons, longevity.

I didn't compare the specs, but it is safe to assume that the 17-40 being an L lens will not be any less quality than the 10-22. Neither did I look at Tamron or Sigma lenses (here I go upsetting people again?)

Alan.

Hmmm, I was interested in the 100-400 but am not keen on the push/pull mechanism nor on the reports of increased dust in the lens due to said mechanism. I am contemplating getting the 400 f5.6 prime which has slightly better IQ than the zoom, although that is to be expected, but far less versatility.

Nah, I don't look at third party lenses

Just a quick note on the point above (for anyone who does not know this) - Canon do not give any EF-S lenses 'L' designation even though the optical quality is comparable in some

They may be optically comparible in some cases. But I think the 'L' does not just refer to optical quality. The 'L' also denotes that the lens has certain weather/dust proof properties, and is constructed to Canon's highest quality standards, out of the best materials, and may also include other things I have no idea about.

All my EF L lenses are metal bodies. All my non 'L' lenses (not EF-S but EF also) are plastic.

Alan.

Err, not me Bazza, well I don't think I have mentioned cash at all, what I spend depends on which way I go with regards to the body, if I go with Pentax I will not need (although I might get) lens. If I go with Nikon or Sony I will need to buy glass.

Snapper

Sorry I misunderstood that you were in a similar situation as Manguish as regards price as well as considering which camera.

Bazza

No Bazza, I'm in a female situation of not being able to make up my mind. Thought I would go for the D90 but now I have read the spec I am not so sure, well not sure at all and now I'm looking at the K20D. Told you at this rate will still be thinking about it this time next year when there will be yet more cameras and more innovations.