The Sigma 85mm f/1.4 DG HSM Art lens is a short telephoto prime lens for full-frame DSLR cameras.
With a focal length of 85mm, it is not exactly "telephoto" enough for sports. But its huge f/1.4 aperture makes it well suited for portraits, weddings and street photography.
The lens features a rounded nine-blade diaphragm that creates attractive out-of-focus areas of the image, otherwise known as the bokeh effect.
The 85mm lens comprises 14 glass elements in 12 groups and uses a Hyper Sonic Motor for quiet autofocusing (AF). There is a manual focus (MF) and AF switch on the lens barrel. However, the MF can be easily engaged by just rotating the focusing ring, even when the autofocus is still in motion.
For this review, I tested the lens with my trusty old workhorse, the Canon EOS 7D. The lens is also available in Nikon and Sigma mounts.
PRICE: $1,688 (Canon mount, version tested; Nikon mount, Sigma mount)
FOCAL LENGTH: 85mm
MAXIMUM APERTURE: f/1.4
MINIMUM APERTURE: f/16
MINIMUM FOCUSING DISTANCE: 85cm
VALUE FOR MONEY: 4/5
In terms of AF performance, this lens is not a speedster. But neither is it a slouch. Getting a focus took around 0.5sec in bright conditions, and around 1sec in dim conditions.
Build quality is superb. The lens feels sturdy, and looks to be able to withstand some punishment.
On the flip side, it is quite large and heavy, compared with lenses that have similar focal length and maximum aperture.
That said, you will probably forget its heft once you see the sheer quality of the images that the lens is capable of producing.
In terms of sharpness, this is probably the best lens that I have tested. The centre of the images stayed sharp from f/1.4 to f/8. Only at f/16 did the centre sharpness start to suffer appreciably. Edge-to-edge sharpness is superb, especially when stopped down to f/5.6.
There is slight vignetting at f/1.4, but you would expect that from such a huge aperture. You will not see it as much of an issue though, if you stop down to f/1.8 and smaller.
Chromatic aberration (CA), or purple fringing, is handled superbly, with minimal CA across the aperture range. A great feat.
To me, the best thing about this lens is the pleasing bokeh effect. If you want to focus on a subject, the out-of-focus areas created by this lens really make the subject stand out. Distant lights appear as pleasing rounded orbs instead of the irregular shapes you get with some lenses.
If I have to nitpick, it would be that the lens is not very versatile. While its huge aperture is a big plus for street and wedding photography, I feel it is best suited to portrait photography.
• Verdict: The Sigma 85mm f/1.4 Art lens is an amazingly sharp lens with beautiful bokeh effect that makes it ideal for shooting portraits.