
Unless you need the extra stop, why not buy both of these lenses? The 17-40 is definitely better than the original 12-24 (not seen any reviews of the mk II) but 12mm is crazy wide on a full frame....I've been going backwards and forwards over these two for the last few weeks, and still can't make my mind up if the extra £s are worth it over the 17-40.
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Then of course should I go third party Sigma 12-24 ( must be FF compatible)
The 17-40 is very usable below f11 - I have some stunning pics at f8 and f5.6. I also have some at F4, but the corners are blurred when you look at them big - partly due to the lens and partly due to the fact that even on short lenses, at wide apertures, depth of field is narrower than you expect from the online calculators.Well I think I have had enough of 17-40 and the mandatory f11+ aperture (for landscape and architecture). That doesn't say anything about 16-35 but one would hope it is at least usable at f/8 or even under! I am using 24-70 for everything I can fit in!
Unless you need the extra stop, why not buy both of these lenses? The 17-40 is definitely better than the original 12-24 (not seen any reviews of the mk II) but 12mm is crazy wide on a full frame....

) The main reason I thought about the 12-24 is I'm on APS-H so that'll be something like 15 or 16 mm at the wide end. The 1.3 crop does mean I've less to worry about the edge softness in lenses of course.The 17-40 is very usable below f11 - I have some stunning pics at f8 and f5.6. I also have some at F4, but the corners are blurred when you look at them big - partly due to the lens and partly due to the fact that even on short lenses, at wide apertures, depth of field is narrower than you expect from the online calculators.
No, it is not as performant at the edges as it is in the centre, but to call it unusable below f11 shows that you chose the wrong tool for the job.
I thought the 17-40 was designed for FF not APS-C? Canon's 10-22 is the recommended UWA for APS-C sensors.
As for the debate on which of the two lenses... When I replaced my 40D (along with the 10-22) I too had the choice of 16-35 or the 17-40, and plumped for the latter due to a) price, b) would be shooting mainly f/8 and above so paying for that extra stop at the low end didn't seem to make sense to me.
It is much easier to design wider angle primes than zooms. A zoom is a compromise - especially a relatively cheap one like the 17-40LIf you had used Zeiss 21mm you would see that it is actually possible to take very sharp landscape pics at f/4 and under!
It is much easier to design wider angle primes than zooms. A zoom is a compromise - especially a relatively cheap one like the 17-40L
You will get shallow depth of field from any lens if you open the aperture and print big enough. It's simply physics and not even Leica or Zeiss can do anything about that.
For me, it's all about value. 95% of the time I'm perfectly happy with the 17-40mm and f4, and 100% of the time I'm happy with the extra £500 in my pocket. I'm sure the 16-35 is better, but most people don't need better, and the 17-40mm is no slouch.
I have been thinking about these two lenses for when I go full frame next year. I do not own a lens slower than 2.8 so the thought of a slow lens is not very appealing to me. On the other hand, if your buying 16-35 for the wide side (like me) how often will you need it to be fast? When I shoot landscapes I never go below F7 or so. Is this how you guys look at it or am I alone here?
Ah, this is where we differ, for me it's all about producing the best quality image I can. If I have top class gear in my bag, then poor image quality is down to me not my tools.
We all have differen priorities and we all spend our money on different things.![]()
If you can't get good images out of the 17-40, you're doing something horribly wrong. The 16-35 is there for its extra stop, and for massive gallery prints.