Sigma 8-16mm f/4.5-5.6 DC HSM
Posted 06 September 2010 - 18:02
Please don't ask questions pertaining to the lens on this thread, rather ask in the Lenses board.
Posted 16 December 2010 - 13:27
In the digital era with plastic barrels this one have to be considered fairly adequate in terms of build quality. The finish is the new variety of the classic Sigma finish, it's sad not to flake as the earlier one used to. I have no idea if that's true yet, what I can say is that it is very comfortable to touch and everything feels very solid, tight and well-constructed. It got a overrideable HSM AF motor, a proper distance-scale under a clear plastic window. The lens cap is basically a ring metal ring/band with a lens cap on the end that fits over the permanent, petal-shaped lens hood. This works but I'm not deliriously happy with it (it goes into a pocket, but it's quite big). Have to mention that it is hard to think of any other solution with such a bulging front element.
Weighing in at some 600 grams and having a very straight and uniform and quite thin barrel it handles well. It's almost identical to for instance the 105 2.0 DC in dimensions. The lens feels a little bit forward-heavy though, but it depends somewhat on which end of the focus scale you are. It's not a true IF design, as the front element moves a little bit (0,5-1cm or so) between the extremes of the focus range and the focus shifts upon changing focal length.
All things considered I actually find it better built than the EX-designated Sigma 17-50 2.8 OS released almost at the same time (one that I also own). Ironic, because the 8-16 does not bear the EX designation since it's not a constant aperture lens.
AF is silent and fast, but hesitates somewhat and seems a little nervous on D90 and D7000 bodies with a tendency to rack a bit back and forth. I think this might be partially down to the considerable FOV and small AF sensors, at least on the D7000. It simply seems it's hard for it to find a contrasty enough subject to focus on, especially at some distance - everything gets so small. At closer distances with larger subjects its much more certain of itself. On the D90 LiveView AF works, not so on the D7000 (lens firmware issue for sure). Sufficient to say, the AF works and does the job without impressing and this isn't a lens used for sports.
Worth to mention is that it focuses very close, down to 29cm according to the manufacturer, in practice I find it's able to focus even a little bit closer, considering the distance from the sensor. Basically one can get as close as ~5cm from the front element, although I haven't made any serious measurement tests. Close-focus ability is important with a lens like this in order to get interesting compositions and perspectives.
The most important aspect of them all, image quality. The "starting-at-8-12mm" rectilinear wide-angle lenses for crop sensors are pushing the most extreme boundaries of what's possible in lens design, still there are a lot of candidates available, some at very nice prices too. This Sigma is the one with the most extreme focal length in the wide end currently available (there are several wider fisheyes though).
Generally these lenses tend to be prone to CA, especially at the widest setting, have soft or "mushy" edges and suffer from field curvature phenomenons. They are often rather sharp in the frame center though. The Sigma overall shows the classic issues for this of class of lenses. No surprise there.
Resolution-wise it is exceptionally sharp already at 8mm in the frame center with good corners wide open at 8mm. When I say sharp I mean sharp as a 50 1.8 at F/5.6 or a 85 1.8 at F/5.6 on a DX body, maybe even better. It's some of the best I've ever seen from the 15-20 lenses I've owned or own. I haven't actually measured it though, it's my poor eyes making the judgement. I'm really impressed by this, I did not think it possible in a DX non-pro grade wide-angle zoom. Stopping down one or two stops improves the edges quite a bit, but the center seems to be as good as it gets from the start. Zooming in the frame gets more even, and the slight vignetting visible at 8mm gets less visible. There seems to be a slight drop of center resolution at 12-16mm at the expense of a more uniform frame. This is nitpicking and not very relevant for practical use. Basically this lens is very usable at the widest aperture setting at all focal lengths and stopping down is good for getting slightly better edges and more depth of field.
At the wides focal lengths, 8-12 in particular, the lens is clearly prone to field curvature. It is possible to get the corners very good, but it requires careful focus to get the best out of the lens. However 2/3rds to 3/4ths of the frame is almost always very much acceptably sharp, it's mainly the extreme edges that can show off the phenomenon.
Contrast is very typical of the latest lens generations, that is, more of it than with older lenses. Color is very slightly warm, but not as much as some Sigmas I've used. Blue skies for instance, pop much more than I expected without a polarizer. Hard to make any direct complaints, but some would perhaps wish for a completely neutral, even "cold" lens such as the 85 1.4D or 105 2.0 DC. For shooting landscapes I personally have no problem with the way this lens renders color, nor would I be afraid of sticking a human being into the frame. They're not looking like they have yellow fever or something
CA is a slight problem at the widest focal length, but without having measured it, I can say that it is better than the 35 1.8G for instance.
Flare resistance is a slightly mixed bag. While this lens clearly have modern coatings that do a good job at minimizing flare, it still got a huge, round front element and a tiny lens hood so if you want it to flare, you'll manage to do so. My experiences from last summer though, is that there's no reason to be afraid of the sun, so to speak, but being aware of the issue and perhaps using a hand to give some extra shade in extreme cases does the trick. This will likely be an issue with any WA lens.
Wide angles such as this lens are demanding lenses to use, at least in terms of framing and composition. With a FOV of around 115 degrees, you can pretty much "get it all in". It does not necessarily make it a better picture. It is very fun and refreshing to shoot with a lens like this, to perceive the world in a different way and get a break from the "boring" normal focal lengths around 35-85mm.
The lens itself is impressive compared to other lenses in the same range, because no lens with such extreme focal lengths will ever be optically perfect (at least no on crop sensors, the 14-24 appears to be a miracle of a lens on FX) and it do it fairly well. I haven't even mentioned distortion, it goes without saying it will exhibit quite some, especially at the widest settings. Lens profiles in ACR helps a lot. Absolute uniform edge to edge sharpness is not going to happen either, but when you hit the sweet spot between focus and DOF, it can look good even in the edges. As of writing this, you are not going to find any directly comparable alternatives, only partially overlapping and somewhat cheaper offerings. The fact that this is a sharp, well-built lens not overly prone to CA, flare and such issues, makes it difficult not to like it.
Some would say that the lack of ability to use a filter is a drawback. Considering the FOV of this lens I find it a moot point. I don't use protective filters and a polarizer don't work well with WA's in the first place. The only true loss is inability to use GNDs. I never use them, but I can see why that would be an issue for some folks.
Should you buy this lens? Only if you are very aware of the different issues (and advantages) that comes with wide angle lenses. It's easy to fall for the gimmick of 8mm, it's much more difficult to put it into purposeful practical use. Will I keep this lens? Yes, both for landscape and tight interior shots I've used it with good success. It's not my most used lens, but it has a place in my bag for certain types of shots.
- Dallas likes this
"I cannot and will not cut my conscience to fit this years fashions."
- Lillian Hellman
Posted 20 August 2011 - 07:39
Almost like a fisheye without the seafood element...
Posted 05 April 2013 - 15:16
I have to report that on my copy, the AF suddenly stopped working. Fortunately it was still under warranty so Sigma replaced the AF unit for free.
What's disturbing about this is the fact that I have no idea why it failed. I haven't dropped the lens or abused it in any way, so I am bothered that the AF unit would just fail for no reason.
0 user(s) are reading this topic
0 members, 0 guests, 0 anonymous users
An appeal to all Fotozones visitors: please help me to keep this site going by starting your gear purchases using any one of the affiliate links shown below:
Amazon.com | Amazon.co.uk | Amazon.de | Adorama.com | thinkTank Photo | DigitalRev.com | OWC | B&H or Donate via PayPal