I have been looking for an intermediate telephoto zoom lens to add to my lens arsenal for wildlife photography. I have owned the Canon 100-400mm lens for a while now but I have never been happy with its sharpness or overall performance and the push pull mechanism for zooming was not very smooth and made tracking while zooming difficult. I was looking at 70-200mm f/2.8 lenses but I felt that I wanted a bit more reach for an intermediate telephoto zoom lens. Someone suggested that I try out the Sigma 120-300 f/2.8 and it looked to be a great idea as it fit nicely in my lens lineup between my wide angle lenses that ranged up to 128mm and my super telephoto Sigma 300-800mm f/5.6 lens.
I tried to find other lenses in that category from all the manufacturers for comparison. The first obvious choice would be against my old f/4.5-5.6 100-400mm lens from Canon. To fairly compare the lenses, I got the Sigma 120-300mm with the Sigma 1.4 teleconverter to be able to cover the extra reach of the Canon lens. The Sigma 120-300mm lens made short work of crushing the performance of the Canon 100-400. Even with the teleconverter on, the Sigma lens outperformed the 100-400mm lens in every way! The Sigma lens is sharper, demonstrated a wicked fast acquisition and autofocus lock even in the dimly lit condition of a football field. The Canon 100-400mm lens consistently lost tracking and hunted with the autofocus!
The Sigma lens was a pleasure to use as I was able to zoom effortlessly by turning the zoom ring while following both the action on a football field or while out in the fields of Yellowstone tracking wildlife. The push pull zoom of the Canon is simply unacceptable by comparison. The tension/lock ring would come loose or stick when I least wanted it to. Zooming while following on the action was clunky at best and remember that I have I owned and used this lens for years! The one major place the 100-400mm has the edge is in its substantial weight savings of about 3.5 lbs when compared to the Sigma 120-300 as well as a price difference of about $1,500 when comparing the two. The weight may be an issue for some but I was able to hand hold the Sigma 120-300 for the entire football game with no issues. Don’t forget that the Sigma 120-300mm lens has a 4 year warranty in the USA compared to Canon’s 1 year warranty as well! I do feel the price difference will be a bigger factor for people when making their choice but given that the Sigma’s performance was far superior in every way, this almost is like a comparison between the major and minor leagues in pro sports.
The closest lens for a true comparison I could find on the market was the Nikon 200-400mm f/4 lens. To make a fair comparison, I put the 1.4 teleconverter on the Sigma 120-300mm f/2.8 effectively making it a 168-420mm f/4 lens. I would use that combination extensively on my tour of Yellowstone and the Tetons and could compare it to my friends’ 200-400mm lens for both sharpness and overall performance when I was out there this past fall. With the Sigma 1.4 teleconverter on the 120-300mm lens performed as well or in my opinion better in both speed of acquisition and focus lock. Sharpness was excellent on both lenses. Because of my lack of familiarity of my friends Nikon body and the 200-400mm lens, we both agreed to call that performance test a tie. Once the teleconverter was removed though, we both agreed that the Sigma 120-300mm lens clearly performed better than the 200-400mm lens in both acquisition and focus lock.
The only advantage of the Nikon 200-400mm lens that I could find was that it had an additional year of a USA warranty. I was able to comfortably hand hold both lens combinations although the Sigma 120-300mm lens comes in about a half pound lighter even with the additional weight of the teleconverter. The biggest difference by far is going to be on the weight of your wallet! The Nikon 200-400mm lens comes in at a whopping $3,300 more than the Sigma 120-300mm lens and the 1.4 tele combined!!! Given that Sigma 120-300 performed better or equal to the 200-400 lens in every aspect, you can save yourself a boat load of money and still get a lens that is the best performing intermediate telephoto zoom lens on the market today! This lens is a perfect choice for those who photograph field sports or nature and wildlife photographers who want a super fast and versatile intermediate telephoto zoom lens. As you can see, there really is no comparison for the Sigma 120-300mm f/2.8 lens but hey…it’s your money.