Ever since I bought the 16-35mm F2.8 L is have been confused.
Most of the shots taken using it were indecently soft in my opinion. Corners are ridden with CA and horribly soft. I discussed this in a thread some time ago and did lots of AF test in order to find out what actually caused all this.
All tests came up fine, but I am still dissatisfied with the optical quality of this L lens.

At one point I beleived the culprit to be my 350D (due the the fair amount of shocks it had to withstand since original purchase in 2005), but Canon Nagoya HQ tests didn't discover any unusual and all images were sharp (so they say anyway).

Finally today I decided to dig out my old Sigma 24-70mm shots and compare. Did a series of shots outside using 16-35mm. I have sold the Sigma about a year ago and so the tests are not really exact match, but close enough.

At the time of the purchase I primarily wanted a good wide angle for landscape photography , but also to use as a portrait/general photography lens. Call it "Jack of all trades".

My biggest gripe with this particular lens is its price-performance ratio. At 1000 gbp (well, I actually paid little over 600) one would expect a great performance, would one not?

Lens certainly shouldn't get all the blame - it takes time and practice for one to be able to take madly sharp photos. However the more and more I use 16-35mm the less and less practical use I see for it in my bag:
Portraiture would be so much better using primes,
16-35mm focal distance does not cover street/candid shots that well,
Landscapes/pano are better done using primes

I am very dubious about selling it - I like the feel of it, the build, the quiet and quick focus . However I am wondering if a 70-200mm F4L IS USM would be more useful for walk around and a Distagon/OM/Leica primes for portraiture and landscapes?
I still would love to own a "great wide"/fish eye but perhaps for a 1.3x sensor (planning to go FF eventually) I would do better with a Sigma 12mm or a Canon EF 14mm f/2.8L?

The bottom line: Am I expecting to much from a 1000gbp L lens (allbeit a wide angle zoom)?

Here are the samples with the links to full res images:
All shots are converted using Adobe's RAW file handler in Photoshop CS2 with sharpening, correction, noise reduction reset to 0! Full EXIF exported to a text layer and can be seen in the full res images.

1. Test 1 at 16mm (focus in a centre sub(ob)ject))

Looks like it could use some calibration. 16-35mm L test shots. Plenty to look at here from one I like.

Gary

The shots look tak sharp. That's bang out of order, I say!!!
I recognise some of them from other 16-35mm threads btw.

I might drop the lens at the Canon coming wednesday.
2 questions pop into my head at this point:
1. Is the calibration service expensive?
2. Once calibrated for 1.3x crop, would it require recalibration for FF?

> At one point I beleived the culprit to be my 350D



I wouldn't consider this lens for this body initially, is this mk I or mk II? Try 10-22 or 17-55 IS.

Breitling: A very good point. Right now the future is a bit uncertain, but I am planning to get a decent camera at a later point (FF or perhaps 2nd hand 1DS(N) MkII).
Suppose if I sell this one now, I can always get a MkII later...

Just bring it in to Canon. I just received my 17-40 back from Canon and my soft left side issues are now a thing of the past.

A few thoughts.

Hard to tell too much from small images.

No lens is absolutely razor sharp at all apertures.

Measurable differences on the test bench do not always translate into visible differences in prints.

On your cropped sensor body you might have been luck (and performance) from the EFS 17-55mm f/2.8 IS.

Dan, I have links to the full res under the resizes posted here - didn't want to hog user bandwidth. If you wouldn't mind having a look at the non-processed full sizes some time, I would like to hear your opinion.

In regard to EF-S lenses, this may well be the case. However, prior to the purchase I read Fred's and others reviews on this site and photozone.de and drew conclusion that the lens is indeed great.

To be honest, if I crank up sharpening to over 120 in CaptureONE the images start looking sharp indeed. If this is how sharp images are taken, I can live with that.
Just to add, I am not worried about vignetting and distortion - my biggest issue with IQ is CA and softness across the frame (corner softness is horrid).

I would send it in for calibration. Have you taken 'real' shots with it (not test shots/brick walls yada yada) and been equally dissatisfied? How about prints? I use my 16-35 on an XTi and it's been very sharp. There is considerable CA in certain situations but I'm beginning to learn when those are and how to fix/avoid them, so i don't consider it significant.

Haven't done any prints at any point except few post card size for the family every now and again.
I have been shooting the the lens since I bought it about 1.5 years ago, so not only test shots.

Here is the example shot I took few months ago:

This is an expensive lens! Since you like the lens it only makes sense to have it calibrated for a fraction of its cost. It appears you are using a crop camera (which cuts off soft edges) so even if you were to buy a new Mk II you would get much better performance.

I was wondering how much the calibration would cost.
But there is no harm in calibrating in, so I can drop it off at Canon tomorrow.

Just discovered some of my test images from about 1 year back, I was bored and was pondering about AF issue.
I have done the similar test before, yet looking at this now reveals one of the issues.

First, 2 samples from 50mm f1.4

1. F2.2

Maybe yours just needs calibration? When I first bought my 16-35 It was admittedly terrible. And not to mention less than 3 months later the new one came out. Kind of surprised me with that one.

Anyways, I sent mine in to canon for calibration and since that day it has yet to let me down. I use it ALL the time on my 1DmkIII, and have used it also on a 5D, 1DmkII, and 1Ds (my former camera bodies) all with fantastic results!

Abram, exactly the same situation here!
I share your pain!
Hmm, only difference is that I'm certain it performs flawlessly on APS-H and APS sensors. So far I haven't seen any posts from APS-C sensors.

But I bugger off to Canon tomorrow and have it checked.

Another thing - same color balance applied across all 4 shots, and mind you 50mm got superb color reproduction compared to 16-35mm.

Went to Canon today. Had a chance to play with a 5D MkII (besides the point)...
They wanted 12.000yen for calibrating 16-35.
I had missus with me and she said "Do you want to pay?" which in her language means "I kill you if you do!", so I say "Sod it for a game of soldiers!".
(the finances are a bit tight atm).
And so the lens will just sit in the bag until I get a job - can be few years in future...

My apologies for the abundance of blunt vocabulary in this post, but I am a tad angry at the moment because "women are from venus"...

Thank you all for your tips and suggestions.

You know, I keep on driving myself nuts over this.
After I walked out of the Canon centre, I kept on shooting and shooting whatever I could and in ISO ranging from 100 to 800, AF and MF and different metering modes...

The results are mind boggling (for me anyway). I find that my MF shots are all soft, while my AF shots are a bit like lottery - some are soft and some are decently sharp, and I don't see any pattern to it.
Occationally, my hand moves a bit when I take a shot and I expect it to be blurry, but it is sharp, and then the other way around....

That day I took quite a few shots at about 1/50sec shutter with F5.6 at ISO800 and most of them seem to look just fine. In the "unsteady hand" shots you can clearly see that the blur is due to the camera motion, and it would be silly to blame the lens for that.

So, last night I decided to shoot a bottle of Suntory - just for fun. Diffused the flash and rigged the reflector (I am very pleased with the lighting in the shot for that matter).
But what I saw in my shots puzzled me even more.

Here is what I am talking about:

AF, Centre Weighted Average Metering, ISO100, F5.6 (full exif is in the fullsize image - link below)
As usual - no processing at all - not even color.
Focus point was around "Whisky".

The focus point area crop