Review: Canon EOS 17-40 f/4L by DxO Mark

[Cali Capture]

I have found this to be a great lens. Opted for this over the 16-32 becuase of price and I use a 24mm 1.4L for low light wide. I'm not a pro landscape photog so this serves my needs wide until something better comes out. I think we all agree Canon could use some help in the superwide range and Ziess's 15mm kind of said the same thing, sans auto focus and afordability!

 

[sdsr]

It's also worth mentioning that lenses designed for crop cameras use tighter tolerances in manufacturing which results in higher image quality (the parts are smaller so this is easier) so generally a lens designed for crop will perform better than a lens designed for full frame. The 17-40mm L is designed for full frame and performs nearly identically to the 18-55mm kit lens, but is more expensive and worse in nearly every way (though it's color and contrast is said to be slightly better, I don't really care personally).

Not entirely sure what you mean by "perform better", but to the extent you're right re image quality, it's only true if you compare the lenses on a crop body, as Neuro's link demonstrated; lenses designed for ff bodies work better on ff bodies, and the comparison tool at the digital picture repeatedly shows that any given ff lens performs better on a ff body than it does on a crop body; it may also show that ff lenses on ff bodies perform better than their crop equivalents on crop bodies. For instance, many a reviewer/commentator raves about the sharpness of the EF-S 60mm macro which, in comparisons, seems to perform better than the 100mm L on crop bodies; Roger Cicala's blurb on the lens says it's one of the rare lenses that make him wish he used a crop body. And it's certainly an excellent lens; but as I recently found out the hard way (i.e., I bought one, though the digital picture would have demonstrated the point had I bothered to check), while it may be light and convenient, it's certainly not as good as, let alone better than, the 100L on a ff body.

As for "tighter tolerances," even if that's true, something is evidently making a lot of reviewers complain about autofocus accuracy on the Sigma. Fantastic image quality is all very well, but you won't notice it when the focus is off. Have those reading this had problems of focus inaccuracy with the Sigma?

 

[Marsu42]

The 17-40mm L is designed for full frame and performs nearly identically to the 18-55mm kit lens, but is more expensive and worse in nearly every way (though it's color and contrast is said to be slightly better, I don't really care personally).

We should pick up that topic again after you try to shoot in snow, rain and sand for some time with the non-L lens - how sharp is your picture if your lens is broken or after you've gone broke yourself after so many repairs?

 

[neuroanatomist]

The 17-40mm L is designed for full frame and performs nearly identically to the 18-55mm kit lens, but is more expensive and worse in nearly every way (though it's color and contrast is said to be slightly better, I don't really care personally).

We should pick up that topic again after you try to shoot in snow, rain and sand for some time with the non-L lens - how sharp is your picture if your lens is broken or after you've gone broke yourself after so many repairs?

Then again, how many white box versions of the rebel kit lens can you buy for the price of one 17-40 L?

 

[Marsu42]

Then again, how many white box versions of the rebel kit lens can you buy for the price of one 17-40 L?

Look here, it's Mr. 1dx talking :-> ... I guess it depends on the type of consumer you are, personally I'm not all too comfortable with a throw-away style and am quite attached to my gear. I don't know the crop lens, but imho the L also has nice handling and an internal zoom which is worth something on its own.

 

[Lee Jay]

When I first bought into dSLRs, I bought four lenses:

17-40L
28-135IS
75-300IS
50/1.8

Since then I've bought and sold:
50/1.4
35/2
Sigma 20/1.8
70-200/2.8L IS I
Tamron 1.4x TC
Tamron 2x TC
Canon 1.4x TC II
100/2

And sold from the original purchase:
28-135IS
50/1.8
75-300IS

The one thing I have left from the original purchase is the 17-40L. It's a terrific lens. I like my Sigma 15mm fisheye more and use it much more, but not because of any flaws in the 17-40L, but because I like the field of view, projection and speed of the fish better.

If you don't need a low-light lens, the 17-40L is great. If you don't need sharp corners on full-frame wide open, the 17-40L is great. The corners are much improved at f/5.6 and very, very solid at f/11. The center and the entire APS-c frame is sharp wide open. Focus is fast and sure, handling is excellent.

 

[Zv]

The 17-40mm L is designed for full frame and performs nearly identically to the 18-55mm kit lens, but is more expensive and worse in nearly every way (though it's color and contrast is said to be slightly better, I don't really care personally).

We should pick up that topic again after you try to shoot in snow, rain and sand for some time with the non-L lens - how sharp is your picture if your lens is broken or after you've gone broke yourself after so many repairs?

Then again, how many white box versions of the rebel kit lens can you buy for the price of one 17-40 L?

Wow, are we seriously comparing the 17-40L to the 18-55 kit lens? The kit lens is good but it's not in the same category. Despite the obvious differences, I can't for example use the kit lens as an UWA on FF therefore there isn't any way we can compare the two optically. I suppose you could buy a cart load of kits for the price of one 17-40L. But so what? I can also buy a few hundred disposable cameras, still doesn't solve my wide angle needs.

Why does everyone hate the 17-40L? We can't all afford 16-35LII lenses.

 

[slclick]

The 17-40mm L is designed for full frame and performs nearly identically to the 18-55mm kit lens, but is more expensive and worse in nearly every way (though it's color and contrast is said to be slightly better, I don't really care personally).

We should pick up that topic again after you try to shoot in snow, rain and sand for some time with the non-L lens - how sharp is your picture if your lens is broken or after you've gone broke yourself after so many repairs?

Then again, how many white box versions of the rebel kit lens can you buy for the price of one 17-40 L?

Wow, are we seriously comparing the 17-40L to the 18-55 kit lens? The kit lens is good but it's not in the same category. Despite the obvious differences, I can't for example use the kit lens as an UWA on FF therefore there isn't any way we can compare the two optically. I suppose you could buy a cart load of kits for the price of one 17-40L. But so what? I can also buy a few hundred disposable cameras, still doesn't solve my wide angle needs.

Why does everyone hate the 17-40L? We can't all afford 16-35LII lenses.

And unfortunately the price difference does not equate the very minor IQ differences, Yes I've owned both.

 

[Lee Jay]

And unfortunately the price difference does not equate the very minor IQ differences, Yes I've owned both.

If you buy a 17-40L as a standard zoom for a crop camera now that plenty of EF-s and other crop options are available, well, you're doing it wrong. It's an ultrawide zoom for full-frame.

 

[neuroanatomist]

If you buy a 17-40L as a standard zoom for a crop camera now that plenty of EF-s and other crop options are available, well, you're doing it wrong. It's an ultrawide zoom for full-frame.

+1 - and that's the point of comparing it to the 18-55/3.5-5.6 IS kit lens or even the 17-55/2.8 IS. Compared to the 17-40L on APS-C, the former delivers not-too-different IQ and the latter delivering better IQ (and an extra stop of light, a broader range, and IS). Yet, many people recommend getting the 17-40L 'in case you go FF maybe someday,' which I think is pretty foolish unless 'someday' is next month.

 

[Lee Jay]

If you buy a 17-40L as a standard zoom for a crop camera now that plenty of EF-s and other crop options are available, well, you're doing it wrong. It's an ultrawide zoom for full-frame.

+1 - and that's the point of comparing it to the 18-55/3.5-5.6 IS kit lens or even the 17-55/2.8 IS. Compared to the 17-40L on APS-C, the former delivers not-too-different IQ and the latter delivering better IQ (and an extra stop of light, a broader range, and IS). Yet, many people recommend getting the 17-40L 'in case you go FF maybe someday,' which I think is pretty foolish unless 'someday' is next month.

Well, it worked for me, but that was when I bought my 10D, which was before the advent of EF-s. A year and a half later, I bought a 5D so it worked. However, if I had to start over again with crop cameras, I'd do exactly what I did at work and buy a 15-85IS instead.

 

[Zv]

If you buy a 17-40L as a standard zoom for a crop camera now that plenty of EF-s and other crop options are available, well, you're doing it wrong. It's an ultrawide zoom for full-frame.

+1 - and that's the point of comparing it to the 18-55/3.5-5.6 IS kit lens or even the 17-55/2.8 IS. Compared to the 17-40L on APS-C, the former delivers not-too-different IQ and the latter delivering better IQ (and an extra stop of light, a broader range, and IS). Yet, many people recommend getting the 17-40L 'in case you go FF maybe someday,' which I think is pretty foolish unless 'someday' is next month.

Ah yes those people who have a cheap entry level Rebel camera with a 17-40L stuck on the end! Yup I agree, unless your "other cameras a FF" and currently out of action you have no excuse! Too cheap to buy a FF camera but has enough to show off with an L lens! (A cheap one at that!) you're foolin no one son!

 

[pj1974]

If you buy a 17-40L as a standard zoom for a crop camera now that plenty of EF-s and other crop options are available, well, you're doing it wrong. It's an ultrawide zoom for full-frame.

+1 - and that's the point of comparing it to the 18-55/3.5-5.6 IS kit lens or even the 17-55/2.8 IS. Compared to the 17-40L on APS-C, the former delivers not-too-different IQ and the latter delivering better IQ (and an extra stop of light, a broader range, and IS). Yet, many people recommend getting the 17-40L 'in case you go FF maybe someday,' which I think is pretty foolish unless 'someday' is next month.

Well, it worked for me, but that was when I bought my 10D, which was before the advent of EF-s. A year and a half later, I bought a 5D so it worked. However, if I had to start over again with crop cameras, I'd do exactly what I did at work and buy a 15-85IS instead.

+1

That's why when I entered the DSLR world, there were fewer options out there for APS-C.

I think Canon (& other manufacturers) are dedicated to 'crop sensors' - there are still plenty of good to great lenses being produced exclusively for APS-C DSLRs (ie won't work on FF).

Hence a number of my lenses I chose specifically as EF-S mounts:
the versatile 15-85mm, superb walk-around / 1 lens-solution, with great quality and
the outstanding Sigma 8-16mm - ultra ultra wide sharp & contrasty too

I frequently advise people to get the lens they need, not 'what they might find useful on a FF'. It might happen to be an EF/ FF lens... but quite often the 'best lens for the current solution' might be an EF-S lens too!

Ok, I also have a 70-300mm L - but that's another story, as none of the other telezooms met my criteria (high optical performance, size/weight to still be portable, full USM, 4 stop IS, and zoom range).

Paul

 

[neuroanatomist]

So you're saying that DxO are criminals because they lied to us saying that the 70-200II is worse than it really is and also because they're saying that the 17-40 is better than it really is?.

No, I'm saying they make mistakes. I do think it's unfortunate and damaging to their credibility that they didn't admit to their mistake with the 70-200 II when called on it, but rather 'circled their wagons', then quietly re-ran their tests and updated the results.

Well I guess this means that they're neither biased towards or against Canon...

I don't think they're specifically biased for or against Canon. But I do think their Scores are biased, and that bias currently happens to favor Nikon. Their Sensor Score emphasizes low ISO performance (2 of the three metrics that factor into the sensor score are considered only at ISO 100), and the score is weighted but they don't disclose the weighting. They base their Lens Score on testing in 150 lux, meaning that transmission (T-stop) trumps other measures (sometimes to the exclusion of logic, is the 50/1.8 really a better lens than the 600/4L IS II?), and that lenses tested on bodies with better high ISO performance or more MP (so that noise is reduced when converted to their 8 MP print scale) are given a better score.

 

[Radiating]

It's also worth mentioning that lenses designed for crop cameras use tighter tolerances in manufacturing which results in higher image quality (the parts are smaller so this is easier) so generally a lens designed for crop will perform better than a lens designed for full frame. The 17-40mm L is designed for full frame and performs nearly identically to the 18-55mm kit lens, but is more expensive and worse in nearly every way (though it's color and contrast is said to be slightly better, I don't really care personally).

Not entirely sure what you mean by "perform better", but to the extent you're right re image quality, it's only true if you compare the lenses on a crop body, as Neuro's link demonstrated; lenses designed for ff bodies work better on ff bodies, and the comparison tool at the digital picture repeatedly shows that any given ff lens performs better on a ff body than it does on a crop body; it may also show that ff lenses on ff bodies perform better than their crop equivalents on crop bodies. For instance, many a reviewer/commentator raves about the sharpness of the EF-S 60mm macro which, in comparisons, seems to perform better than the 100mm L on crop bodies; Roger Cicala's blurb on the lens says it's one of the rare lenses that make him wish he used a crop body. And it's certainly an excellent lens; but as I recently found out the hard way (i.e., I bought one, though the digital picture would have demonstrated the point had I bothered to check), while it may be light and convenient, it's certainly not as good as, let alone better than, the 100L on a ff body.

As for "tighter tolerances," even if that's true, something is evidently making a lot of reviewers complain about autofocus accuracy on the Sigma. Fantastic image quality is all very well, but you won't notice it when the focus is off. Have those reading this had problems of focus inaccuracy with the Sigma?

Right FF Lens on Crop < Crop Lens on Crop < FF Lens on FF

There are tons of examples of this:

24-105mm on 7D < 15-85mm on 7D < 24-105mm on 5D3

100L on 7D < 60 EF-S on 7D < 100L on 5D3

17-40mm on 7D < 17-55mm 2.8/18-35mm 1.8 on 7D < 17-40mm on 5D3

16-35mm 2.8 on 7D < Sigma 8-16mm on 7D < 16-35mm 2.8 on 5D3

Although there are some exceptions.

If you buy a 17-40L as a standard zoom for a crop camera now that plenty of EF-s and other crop options are available, well, you're doing it wrong. It's an ultrawide zoom for full-frame.

+1 - and that's the point of comparing it to the 18-55/3.5-5.6 IS kit lens or even the 17-55/2.8 IS. Compared to the 17-40L on APS-C, the former delivers not-too-different IQ and the latter delivering better IQ (and an extra stop of light, a broader range, and IS). Yet, many people recommend getting the 17-40L 'in case you go FF maybe someday,' which I think is pretty foolish unless 'someday' is next month.

Ah yes those people who have a cheap entry level Rebel camera with a 17-40L stuck on the end! Yup I agree, unless your "other cameras a FF" and currently out of action you have no excuse! Too cheap to buy a FF camera but has enough to show off with an L lens! (A cheap one at that!) you're foolin no one son!

Yep that's why I introduced it as "this is something newbies often mix up", the question was to compare a 17-40mm L versus a 18-35mm ART on crop. The 17-40mm L on crop has basically identical performance to the 18-55mm kit lens. while the 18-35mm ART has substantially better performance than either when limiting the comparison to crop only.

Although I've also seen some serious photographers establish that the image quality is ever so slightly better on the 17-40mm over the 18-55mm on crop, so it's still a slight, very slight upgrade. But this argument only made sense when the 17-40mm was 2/3rds the price of the 17-55mm. Now pricing is identical between the two so the choice is clear, unless you need weather sealing or have other special purposes for the 17-40mm on crop, such as sharing the lens with full frame or something else. But I always advise like others to get the lenses that work best now, not later.

 

[Radiating]

I have a theory that DXO has been getting specially selected copies with perfect tolerances from Canon. Several of their tests are way better than average. Certainly not impossible, but definitely not "average" from what I've seen.

No doubt that explains why their initial testing of the 70-200/2.8L IS II showed that it was not quite as good as the 70-200/2.8L IS that it replaced… :

http://www.dxomark.com/Reviews/Canon-EF-70-200mm-f-2.8L-IS-II-USM-measurements-and-review

Can you point to some examples (other than the 17-40L, which as I stated, I think DxO's measurements are way too good to be even a cherry-picked copy)?

Their 17-40mm L is a factory freak (meaning unusually good copy)
Their 50mm 1.2L is also a factory freak

Roger Cicala tested over 30 different copies of the 50mm f/1.2L

and got these results wide open:

The results of DxO Mark returned on the 50mm 1.2L were only achieved by 1 lens that Roger Cicala tested out of 30 copies. There is a massive 25% difference in image quality with a factory freak copy on the 50mm 1.2L, so the fact that DxO Mark got a best out of 30 copy on a lens with a lot of copy variation seems suspicious. This test also seems suspicious, again they are getting a good copy of a lens with a lot of copy variation.

I do agree with you though that while, DxO is a useful source of data, their scores, and ways of ranking products using that data are really nonsensical. It's like adding up a car's interior volume, multiplying by horsepower, and dividing by the price to get a "car mark" score. :

The only DxO Mark score that I like is their low light score, which tells you what the maximum acceptable ISO is for most cameras. Other than that it's only worth looking at the data and ignoring the scores.

But it is nice to get a company that collects data on cameras, and I think people don't appreciate that enough. There's a lot of useful data when you get down to it.

 

[ahab1372]

Didn't Roger also write something on his website that Imatest values should not compared between different testers/labs? I think you are just doing that. I doubt that DXO and lens rentals have an identical test setup.

 

[Rick]

DXO is such a reliable site... ;D

http://www.dxomark.com/Lenses/Compare/Side-by-side/Carl-Zeiss-Distagon-2.8-21mm-ZF2-Nikon-on-Nikon-D3X-versus-Carl-Zeiss-Distagon-T-21mm-f-2.8-ZE-Canon-on-Canon-EOS-5D-Mark-II___334_485_326_483

Sad that you believe this makes some kind of statement. For those interested in the facts:

http://www.dxomark.com/en/Reviews/DxOMark-Score

Having shot with two 5D2s for a couple of years until I replaced one of them with a D3x which I still own, I'd say the overall score differential is about right.

 

[Rick]

Having owned the 16-35, 17-40, 16-35 II in that order and I currently own the Nikkor 14-24G, I'd say the 17-40 is at the bottom of the UWA zoom pack in terms of absolute IQ. Can one make likable images with it? Of course. If I couldn't, that would be saying more about my abilities than the lens'. But let's be honest. The single best "feature" of this lens is price.

 

[neuroanatomist]

[But I do think their Scores are biased, and that bias currently happens to favor Nikon. Their Sensor Score emphasizes low ISO performance (2 of the three metrics that factor into the sensor score are considered only at ISO 100), and the score is weighted but they don't disclose the weighting.

That's understandable because low ISO is where the sensor's best performance is (or should be) and everyone that I know wants the best possible IQ in their pictures.

Similarly, our tendency is to shoot at the lowest workable ISO because the lower the ISO, the better the IQ. Even people that shoot at ISO 6400 regularly only do so because they have to, not because they want to. If the lighting was such that they could use ISO 1600 instead and get the same outcome, then they would.

It may be logical but it's still biased. It would be logical to bias a 'car score' toward fuel economy (because everyone wants that, right?), which usually goes hand in hand with smaller engine capacity and lower curb weight. But if you need a high towing capacity or room for three car seats, that bias works against you.

You prove my point when you state that shooting at ISO 1600 is better than ISO 6400. Neither of those is ISO 100. Maybe 95% of your shots are at ISO 100, but the majority of my shots are higher than that. If my average ISO is 1600, and 'sensor A' performs better than 'sensor B' at ISO 100, but worse at ISO 1600, then DxO's biased Score is not helpful to me.

Bias isn't always bad...as long as the nature of the bias is known. But a biased score with unspecified weightings is not useful. Do you really believe that a D800 delivers better IQ than a Phase One IQ180?

They base their Lens Score on testing in 150 lux, meaning that transmission (T-stop) trumps other measures (sometimes to the exclusion of logic, is the 50/1.8 really a better lens than the 600/4L IS II?), and that lenses tested on bodies with better high ISO performance or more MP (so that noise is reduced when converted to their 8 MP print scale) are given a better score.

It comes down to how do you define "better."

DxO measure a lens in terms of its ability to reproduce an image. For the software that they write, they don't care about how well the IS works or if it breaks when you take it off the camera for the 10th time. Their focus is on how well the lens is able to produce an image so that they can make the appropriate corrections in their software. They also don't care as much about price. If you care more about the build, whether a lens is weather proof'd, etc, than you do about the IQ then yes, the DxO scores are meaningless.

"DxO measure a lens in terms of its ability to reproduce an image.". Yes, they do - and as I've repeatedly stated, their measurements are useful (when correct). Of course they're not measuring IS or build quality for lenses, any more than they measure fps or AF performance for their sensor score - no one has suggested that, and your reference to it is a red herring.

But, while DxO measures lenses in terms of optical performance, the DxO Lens Score has very little relationship to those measurements, but instead is based primarily on performance in 150 lux illumination (e.g., dim warehouse light levels). If their Score primarily represents a lens' 'ability to reproduce an image' does it make sense to you that the 50/1.8 II can reproduce a better image than the 600/4 II? Would you agree that lens performance generally improves when a lens is stopped down a bit? If so, does it make sense that the 50/1.8 II is, "Best at 50mm f/1.8," as DxO states right next to the Lens Score?

Furthermore, sensor performance influences the Lens Score, as in tron's example of the same Zeiss lens in Canon vs. Nikon mount, with optical metrics the same (or very marginally better on the Canon) scoring 10% higher on Nikon.

Sure, you can define "better" as better for shooting in a dimly lit warehouse. But that makes little sense as a basis for a Score used to compare lenses - an f/1.8 lens doesn't 'reproduce an image' better than an f/4 simply by virtue of transmitting more light. Image Quality is not defined primarily by a lens' maximum T-stop. The Lens Score is biased and misleading, especially when DxO sticks that score on top of a list of optical metrics, which implies those metrics are somehow 'summarized' by that score when that's not at all the case.

I like DxO, I use their RAW converter as part of my workflow, and their sensor and lens measurements are useful, too. But...their Biased Scores are just that...BS = bovine scat = cow excrement.