Canon 24-70 mm f2.8 L vs Canon 24-105 mm f4 L IS

24-70 vs 24-105
There is probably no more frequently asked question on photography forums than what is the better lens when comparing Canon's two professional mid-range zooms. These discussions are invariably circular and pretty much get nowhere, like an old married couple arguing: "he said..." "she said..." "he said..." etc, ad infinitum. Typically they end up confirming what we already know at the start: the Canon 24-70 f2.8 L is one stop faster and somewhat bigger; the Canon 24-105 f4 L has image stabilization (IS) built into the lens and has more reach on the long end. They are both built like tanks. They both cost a similar amount (maybe not an arm and a leg when you consider their quality, but the equivalent of a hand and a few toes anyway). One's tempted to say, "You pays ya money and you makes ya choice."

But what choice should you make? And I guess that is the better question – rather than which is the better of the two lenses – and it's the reason that I have even bothered to step into the fray and add my own six eggs.

I had not had the Canon 24-70 f2.8 L long, when Canon announced the 24-105 f4 L IS. Immediately I was struck with something that felt like regret. Had I just wasted my money? The 24-105 sounded perfect for me. When I am photographing animals, I prefer to work without a tripod. I do a lot of hiking and spend a lot of time in the field, and the difference in weight (280 g) would certainly be noticed and welcome. And, when photographing animals, you can never have too much reach at your disposal – and although I have other lenses to cater for the close-ups, having an extra 35 mm reach without the need to change lenses could be a real advantage. Consequently, I got the 24-105 with the intention of replacing the 24-70.

Try as I might to love my 24-105, there has been little chemistry between us, and I find myself usually bypassing the younger and sleeker 24-105 in favor of the big and fat and older 24-70. As I explained above, I am practically a poster boy for the type of user that should lust after the 24-105. So what's the issue? Okay, I'll come right out and say it: I prefer the output from the 24-70. But, even if that is enough justification for me to turn my back on such a seemingly attractive offering from Canon, surely you need to know more when making your choice of the perfect lens to partner with.

Quantifying the differences in output is certainly difficult. On the boards, the consensus seems to be that both lenses are equally sharp and have equally good color and contrast – with what differences that exist perhaps being a consequence of the variations that can occur between individual copies of the lenses. I wouldn't really argue against that, although I'd probably give the edge to the 24-70 when comparing my copies – but that is not where the main differences between the output of the two lenses lie.

I shoot a lot in the Antarctic. Considering my two most recent trips to Antarctica: on the first I opted to take the 24-70, on the second the 24-105. While both lenses performed well, when it came to sorting through the images produced by them, I had more "keepers" from the 24-70. By "keepers" in this regard, I don't just mean that the image was sharply focused and correctly exposed, I mean that the image overall had a certain quality that viscerally – from somewhere deep inside – made it noteworthy. We all have internal barometers that tell us when we really like something; it's that initial reaction. The hardest part is to identify what it is that causes that reaction. The moment you start to analyze it, you lose the spontaneity that is a part of it.

Don't get me wrong: the 24-105 is capable of producing excellent images. I really like this one, for example.

Certainly, the 24-105 has much more distortion apparent at the wide end. This can be a problem, but it only occasionally raised its ugly head in the shots I'd taken. Certainly, the 24-105 is more prone to vignetting than the 24-70. This, again, was not so major as to account for the differences in my reaction to their respective images. On balance, I believe that the thing that really gives the images produced by the 24-70 their "wow factor" is the bokeh. Somewhat contrarily, it is the out-of-focus areas of an image produced by the 24-70 that really make the in-focus areas shine.

For what it is worth when you are making your choice, here are my recommendations:

• If image quality (IQ) is of paramount importance to you: get the Canon 24-70 f2.8 L.

• If portability and weight are an issue: get the Canon 24-105 f4 L IS.

Think of the IS and the bit of extra reach on the 24-105 as welcome bonuses. In of themselves, I don't find much of an argument for compromising IQ. If I need more reach than the 24-70, I can use another lens (if range of focal lengths were the primary determinant of our buying choices, then we should all be shooting with the 28-300 and nobody should be using primes). A faster shutter speed is better for freezing movements of animals than is IS, and light levels have to be pretty low before I cannot handhold the 24-70 and get an acceptably fast shutter speed to counteract handshake (I do value IS: it's just that its relative value tends to increase with focal length). But for convenience's sake, I am prepared to make some compromises.

Consequently, I keep both the 24-70 and the 24-105. The 24-70 is definitely my love, my lens of choice. However, I retain and use the 24-105 for travel mainly, when weight and space are at a premium. There are times when not-so-good can be better.

Shot with the 24-70 wide open

Addendum (a few more years of experience)

With the benefit of four more years of experience of using these two lenses, my conclusions above have largely been reinforced – but with riders. The truth is that neither of these lenses is perfect. Each is compromised in some way and, truthfully, these compromises are greater than one might expect given their price and reputation.

The 24-70 2.8 L has since been updated to version II – and while I have not used the new model, I understand it is a better performer than the original 24-70 2.8 L. These comments pertain only to the original version.

There is a lot more to a lens than its resolving power, and both these lenses (the 24-70 and 24-105) benefit from the Canon L designation with rock-like build and great contrast that can render a pleasing result. When it comes to resolution though, the results are a bit of a mixed bag. While my initial impression was that the 24-70 2.8 L is slightly sharper than its svelte brother, extensive use and testing has shown that is not always the case. Summarizing my experience:

• At the wide end (24mm), the 24-105 is sharper than the 24-70 at f4 in both the centre and extreme corners of the image. The 24-70 does improve by stopping down so that by f8 there is little between the two lenses – it is worth noting, however, that the 24-70 at f2.8 is disappointingly soft in the extreme corners.

• At the long end (70 mm), the 24-70 is quite a lot sharper than the 24-105 in the centre at f4, with its centre sharpness at f2.8 being on a par with the 24-105 at f4. Sharpness in the extreme corners is similar between the two lenses with, if anything, a slight edge to the 24-105. The centre performance of the 24-105 continues to deteriorate with greater reach, with sharpness at 105 mm dropping even further from the modest performance at 70 mm.

The extra reach of the 24-105 comes at a performance cost, then, that makes it okay at a pinch at the long end, but if you like using medium telephoto lenses for landscape work, as do I, you’ll be underwhelmed by the results. The 24-70 is much better in that regard. At the wide end, the 24-105 has it all over its bulky brethren in terms of sharpness, but there are another couple of foibles that make it, even then, the less appealing option for me.

Firstly, if using the lenses at f8 or thereabouts (which is often the case at such wide angles), the performance of the two lenses is very similar, BUT, when you want the bokeh to separate subject from background, the 24-105 can’t live with the 24-70’s f2.8 abilities - and to be honest, in such situations it mostly does not matter that the extreme corners are soft as for the most part they will not be the focal point of interest anyway. While the 24-105 does have the advantage of image stabilisation, the 24 mm end of the lens is when it is least useful.

The most annoying feature of the 24-105 for me, however, is the distortion the 24-105 generates at its short end. While I commented on this in my original review above, I largely dismissed it as irrelevant to the sort of photography I was doing at that time in the Antarctic. Since then, however, my words have come back to haunt me: on a couple of assignments, when I opted to take the 24-105 (largely because it was being used also for filming, when the image stabilisation is a definite advantage), the distortion at 24 mm significantly compromised the images I was able to get. For any type of work involving architectural subjects or critically straight lines where you need to shoot wide, I do not recommend the 24-105.

Other Options

Over the last four years there have been some major advances and developments in digital photography. Improved sensor performance is one area of significant change. It has allowed full-frame sensors like those used in the Nikon D800 to enter the realm of the medium format user, and it has also allowed smaller formats in such cameras as the Olympus OM-D E-M5 and the Nikon V1 to punch above their weights with respect to those things that have traditionally been the archilles heel of the smaller formats: noise and dynamic range. One of the benefits that these “designed for digital” formats can have is through the purposely built lenses that are made to accompany them. Olympus and Panasonic made much of the Four-Thirds sensor size when they first launched it, in large part because of the telecentric nature of lenses designed to work with it, which promised not only smaller lenses, but optically superior lenses.

The top Four-Thirds lenses from Olympus have often been criticised for being almost as large as their full-frame equivalents, while few criticised their optical performance. However, now the mirrorless Micro-Four-Thirds system (which uses the Four-Thirds sensor size) is delivering lenses that are both small and optically excellent. Just how good? Compare the extreme corner performance of the Canon 24-70 and 24-105 against any of the top flight Four-Thirds zooms (e.g. the Panasonic/Leica 14-50 f2.8-3.5 or the Olympus 12-60 f2.8-4) and Micro Four-Thirds zooms (e.g. Panasonic 12-35 f2.8) [note: because of the 2x crop factor of the Four-Thirds sensor, these are the equivalent focal lengths on full frame of 28-100, 24-120 and 24-70, respectively] and you will start to feel a little cheated by the Canon L lenses. These telecentric lenses are sharper in the corners and they are sharp from wide open.

Updated Conclusion

Hence, my conclusion remains largely unmodified when considering which of the Canon L zooms to get. If best performance is your priority, pick the Canon 24-70 f2.8L – and assuming the version II is even better, get that instead. If size and convenience are the top priority, get the 24-105, although – and this is more personal advice than it is a rider – if portability is truly your top requirement, you might like to consider why you are not using the likes of an Olympus OM-D E-M5 with a Panasonic 12-35 f2.8 lens instead. I’ve been comparing just such a set-up with a full frame Canon 5D Mark II and 24-70 f2.8L and the results have been quite surprising.