Sigma 24–105mm f/4 Art: Convenience in Art
Shridhar Kunte tests the Sigma 24–105mm f/4 DG OS HSM Art lens to see if the Art branding can extend its magic to full frame zooms as well.
As the megapixel war is becoming intense, there is a clear need for lenses that will give full justice to high-resolution sensors that are now going well over 20 and even 30MP. While both Canon and Nikon have proprietary f/4 standard zooms, Sigma’s Art series lens is expected to maintain the quality, while being at a lower price. To see whether the lens fulfills this promise well, I decided to test it on the Canon EOS 6D.
The lens is primarily meant for full frame users. Of course, cropped sensor owners can mount the lens, but it does not make much sense as there are less expensive, lighter options that cover similar focal lengths for them.
With a zoom ratio of 4.3x, the lens construction is extremely complex. The lens has as many as 19 elements in 14 groups, out of which seven are made of special optics. These elements are coated with a special coating that improves light transmission and offers superior colour consistency and reduces flare. The overall length of the lens varies while zooming, but focusing is completely internal. The Hyper Sonic Motor allows faster noiseless focusing with full time manual focus override. The lens accepts 82mm filters. This is a real pain in India, as 82mm filters are not only expensive, but also difficult to find.
High quality engineering plastic and metal is used extensively in the construction. With the overall weight of 885g, this lens is heavier by 215g, as compared to the Canon 24–105mm f/4 IS! This, in conjunction with the metal mount, gives an overall robust feel.
So while the Sigma harmonises well on the 5D Mark III, it feels rather odd on the smaller bodies like the 6D. In hand, the lens feels well built and solid. I can easily say that the build quality is closer to a Zeiss lens, rather than a Canon.
When the lens is at 24mm focal length, it shrinks to a decent size, thus making it easy to carry in a bag. The manual focus ring is placed behind the zoom ring and is rather narrow, but it offers good damping. The focus ring is having an angle of rotation of approximately 95° in which the lens covers entire focusing range.
The zoom ring is large enough to grip. While carrying the 6D with the lens on a Black Rapid strap, I did not encounter any lens creep. The focusing scale is cramped in a single small window, but the magnification scale is absent. Unfortunately, there is neither DOF indication nor infrared focus index.
On the 6D, the autofocus is reasonably fast, but not as quick as the proprietary lens. That said, the AF is very accurate and the images produced by the lens are tack sharp. The minimum focusing distance that this lens offers helps get impressively close and still get excellent results. The sharpness is very good at the centre throughout the entire aperture range.
I was a little worried to see the light falloff while shooting wide open at 24mm. It is most visible at the mid range of the focal length. If this is of concern to you, you must stop down by at least two stops or correct the image in software.
The against-light performance is exactly what we expect from an Art series lens—top notch. There is some visible chromatic aberration, but this is only in the RAW files and only in extreme situations.
At 24mm, the lens exhibits noticeable barrel distortion. When zoomed in to 35mm, the distortion eases out. Finally, at 105mm, pincushion distortion sets in. The bokeh is smooth.
Along with quality the other main factor while buying the lens over the camera’s kit lens is the cost. Here the Sigma lens is priced at Rs 69,990 which is slightly lower than Canon’s equivalent and much cheaper than Nikon’s 24–120mm. Of course, Canon users who are buying a new camera can buy the proprietary lens as a part of the kit, which works out to an even cheaper deal.
If you fall in that category, you can stick to the Canon kit lens, but for others, the quality combined with the superior build and lower price tag make this an effective package deal. It is not a flawless lens, and not nearly as good as the other Art lenses. But it does a great job of combining convenience with good quality, as long as you keep its optical flaws in mind and do not mind the extra weight.
Stabilisation, silent HSM motor, convenient zoom range, filter diameter rather large
Excellent sharpness, decently fast AF but not the best, vignetting visible, some distortion
Brass mount, metal and high grade plastics
Wide rubberised rings, large AF/MF switch, full-time manual focus override
Warranty & Support
Limited number of service facilities
Value For Money: 3.5/5
Who should buy it?
Full frame owners who need convenience and did not buy a standard zoom with the kit.
At the price for the kit package, the Canon 24–105mm is a better deal, but if you bought your camera body only, you should strongly consider this Sigma.