Perhaps you’ve heard of Sigma’s Art series of lenses? After years spent making relatively mediocre lenses, the Japanese manufacturer has stepped up their game to create some beautiful gems that outshine the lenses made by the camera companies themselves.
The 50mm f/1.4 and the 35mm f/1.4 were both on my list, but I seem to have ended up with the Sigma 24-105mm f/4 Art lens, and while my artistic conscience might try to persuade me of the superiority of prime lenses, it’s currently my favourite.
Zoom versus Prime Lenses
The prime lenses I like are big and heavy, because of the large maximum aperture. Assuming that my assistant carried them everywhere and could change them instantly, I might be less keen on the versatility of the Sigma. But that’s not the case, and often a zoom is the better choice. Zoom lenses used to be too much of a compromise. The Sigma 24-105mm lens compromises just enough, and delivers a lot. It’s a slow lens at f/4, but the optical stabilization is good, and the high ISO capabilities of current cameras means that I’ve never felt too limited by this. It’s certainly a compromise compared to a prime, but at f/8, I bet you couldn’t tell the difference. The bokeh for this zoom, necessarily a matter of personal taste, and not as amazing as some of the prime lenses, is good enough too.
But I want Nikon/Canon, I want the best…
Canon has an equivalent 24-105mm f/4 lens from their premium L-series. It’s a versatile lens, and I know several professional photographers who use it almost exclusively. I use Nikon, but I’ve seen comparisons that demonstrate that optically, the Sigma Art series lens is sharper. The Canon is weather-sealed though, which the Sigma is not. Nikon has a 24-120mm lens that isn’t as sharp as the Sigma either. If image quality is what you want most, the Sigma is the best among the three lenses. Of course, both Nikon and Canon make 24-70mm lenses that are sharper, though at the expense of the longer telephoto reach.
Why choose the 24-105mm focal length over a 24-70mm?
Forgetting prime lenses, the main competition for my affections were the Nikon 24-70mm and the Tamron 24-70mm lenses. There’s also a Tokina 24-70mm available that I didn’t consider. I decided against the Nikon because it doesn’t have optical stabilization (OS). While the larger f/2.8 aperture is attractive, it doesn’t make as much difference in low light for static subjects as the OS on the Sigma. Moreover, the stabilization is useful for on-the-go filming too. The Tamron however, has the larger f/2.8 aperture and is also stabilized.
I chose the Sigma lens because of the longer reach. 70mm, for me, is not as flattering for headshot portraits as the 85-105mm focal lengths that the Sigma provides. I find I use the extra reach quite often. On the other end, 24mm seems to be wide enough for the majority of situations on a full-frame body. If I need a larger field of view, or shallower depth of field, I can often stitch multiple photos together.
Space for a whinge
It’s not a perfect lens, and there are a few omissions that I’d like to have a moan about to help round out the My Favourite Lens angle. While the lens is sharp, it does have noticeable distortion and a fair bit of vignetting too, especially at larger apertures. This is an issue that I’m happy to accept because the RAW photo conversion software does a good job of correcting these flaws.
The bigger issue is the lack of weather sealing, which I’d have happily paid a bit more for. It makes you think twice when photographing in the rain or by the sea. The thoughts are usually, “I wonder if the lens will survive this?” and, “I wonder if I’ll buy the Nikon if it doesn’t?”. Showers aside, the lack of weather sealing does mean that the lens attracts more dust – it veritably sucks it up, and distributes it liberally amongst its inner optics, safe from my lens cleaning cloth. The build quality is good, but not as solid as the Canon L-series lens, for example, and after some abuse, the focal length numbers on mine wore off as they are not etched into the lens. Sigma were good about fixing this though.
Conclusion
I’ve tested a huge number of lenses, and also read pretty much most of reviews of the others, to keep up to date. I chose to buy the Sigma 24-105mm f/4 OS, and it lives on my camera pretty consistently. It’s photographed a range of genres from landscapes, to portraits, and fashion, and the image quality has been good.
As photographers, there’s a tendency to fuss over MTF charts and such like; but having the right focal length available immediately is far more important, and as for overall sharpness and rendering compared to primes, it’s usually only experienced photographers who, occasionally, may notice the difference.