I've been intending to write this review for months now, ever since this lens provided me with perfect performance during an unexpected encounter with a deer in hot pursuit of a coyote.
I was particularly excited about testing this lens for urban wildlife. I mostly use a 500mm for wildlife but it would just be ridiculous to take that out in a city park. I'd get way too much attention from both passers-by and muggers. The best walk-around lens for urban wildlife is something rugged that covers a range between 100mm to 400mm and this lens offers it. The 120-300mm range is great on any camera, and when I put it on my Canon 7D, I get the equivalent of 192mm-480mm. Another reason this lens is so appealing is that it shoots at f/2.8 across board. Considering I'm usually out at dawn for urban wildlife, that's a huge plus - I actually stand a chance of capturing quickly moving animals in low light!
I have to admit that my first experience with this lens was a little rocky. The company sent me a copy that had problems with soft focus. Even with micro-adjustments, the lens wouldn't provide sharp focus on its target. I asked about the issue and they let me know that's indeed a problem with the copy, and sent me a different copy. Likely, quite a few people had tested the first copy before I got my hands on it, so the soft focus could have been a problem arising from being banged around during multiple shipments. I can't say for sure. But what I can say is when the second copy arrived, it looked banged up and yet worked perfectly. So this lens can likely take a beating and still function just fine (a necessity for those shooting wildlife) provided you get a copy that works correctly.
The performance of the second copy quickly wiped away the reservations I had with this lens based on a frustrating first experience. In fact, by the time I had to send the lens back, I really, really didn't want to part with it.
Just as most lenses tend to be their sharpest a couple stops down from wide open, this lens is sharpest when shooting f/5.6 to f/8. I found if I opened up to f/3.5 at the widest, I was still happy with the results, though I was almost never happy with images shot at f/2.8. But he fact is, even if wide open doesn't produce the best results, this is not really a deal breaker. More important to me is that I have that option if I really need it, and I can shoot at any focal length without having to stop down.
Another issue is that while this lens is wonderful for low light, the speed at which it can find and lock on to and follow subjects in low light can be a bit sluggish. Considering that's an important part of my shooting, I found this to be a bit of a problem. But again, this is not unusual in telephoto lenses and it is not a deal breaker. There are ways to get around this problem by ramping up tracking speed in your camera, adjusting the focusing distance on the lens, and of course, if the situation calls for it, manual focusing. If you can get your settings correct, then this lens can lock onto subjects quickly enough, even in the shadows of underbrush at twilight.
Speaking of subjects in the shadows of underbrush at twilight, let's move on to some sample images.
I used this lens when photographing a family of wild gray foxes. They typically don't really get moving for the night until dusk when light is quickly disappearing. This female was sitting under a tree just after sunset. In order to get any shot through the weeds, I had to lie on my back in an awkward angle, handholding while basically maintaining a half-sit-up. Zoomed all the way in to 300mm and opening up to f/3.5, I could manage to get only about 1/160 of a second as my max shutter speed and that was after bumping the ISO up to 4000. Considering the circumstances, this shot really shows how great the image stabilization is for this lens, as well as the kind of possibilities that open up for shooters working with moving subjects in low light. I'm sure the image would have been sharper if I'd had my gear on a tripod, or propped on a log or rock. Most of the time, this lens is one that a shooter will use handheld, not on a tripod, so the fact that you can get this kind of performance from a lens even at a low shutter speed and with a bit of shake says a lot about it.
To note, at 7.47 lbs, this thing is heavy. I will fully admit to having a little soreness in my arms and shoulders the day after I first used this lens. But, it wasn't so bad once I got used to it and knew how to balance the weight, and a little accidental exercise is never a bad thing. However, I couldn't hold this up for long periods without my arm starting to get a bit shaky. And, the weight did make it a little awkward to zoom all the way from 120mm to 300mm as I couldn't do that in one smooth motion and still balance the lens. On a tripod, neither of these things are an issue, but again, I doubt most folks will use this with a tripod.
After I pushed the tracking speed as fast as it would go, I could follow speedy subjects all over the place without a focusing issue, even at dawn. This coyote was photographed just as the sun was coming up. I was able to maintain perfect focus on her as she trotted across my path.
Below is a different coyote, shot just after sunrise but in the shade of trees. The lens didn't have an issue quickly locking focus.
Below are sample shots with the full image and 100% zoomed in so you can see the image quality:
Despite a slightly rocky start, my overall experience with this lens was really positive. I wouldn't hesitate to recommend that anyone looking for a telephoto zoom for sports and wildlife should look into this beast. But I would recommend that folks rent a copy for a couple weeks to make sure you love it first, or make sure you buy it from a company that has a good return policy so you can test out sharpness when the lens arrives. It wouldn't surprise me if people choose this beautiful lens over any others with a similar range. The price point of $3,600 may feel a little expensive to some, but it is a really reasonable price for what you get with this lens. It offers so much flexibility in shooting, and you can tell Sigma spent a lot of time and effort in perfecting one amazing piece of equipment. All in all, this is something I would love to add to my kit one of these days.