Top positive review
5.0 out of 5 starsSharp and about the right weight for hikers!
Reviewed in the United States on May 22, 2017
Later edit:
I also bought the Sigma 150-600 Contemporary because it is not much more expensive than the 100-400mm and the extra reach seems to be always useful. The weight difference between the two lenses did not seem like a lot initially, but then I went on a full day trip to Point Pelee National Park for birding, and boy did my hands start hurting after an 1-2 hours of operating the 150-600m. In the end, I had to switch to the 100-400 because my arms fatigued after a while, and I just couldn't handle the 150-600 well without a tripod. I will return the 150-600, and will keep the 100-400 lens.
I also tried the 1.4x TC 1401 with the 100-400, and in a bright enough environment, autofocus works well on my D500 at f/9 without any real drop in image quality (to my eyes).
After customizing the OS and AF of this lens with the USB dock, things seem to be working a lot better. I changed the OS mode to "moderate" which resulted in noticeably more stable viewfinder images over the "standard" mode that the lens comes programmed in. The "dynamic" mode gives the most stable viewfinder, but is jumpy when you move the lens around (this can also be seen on Sigma's videos on lens customizations). The performance with changes is exactly as described in the Sigma videos. I am consequently updating the review to 5 stars. I changed the autofocus mode so that is focuses faster. I still think the Nikkor focus is marginally better in low contrast situations, but this does not bother me as much. To my eyes this lens is sharper on my D500 than the Nikkor 70-300 IF-ED. Also the minimum focus distance seems smaller than 1.6m if you adjust it manually, which is a plus!
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Original review:
This is a short initial review for a potential buyer. This lens is sharp (for my purposes) at all focal lengths, especially at 400mm. I recommend purchasing this lens with the Sigma USB dock. While the in body Optical Stabilization (OS) on this lens is great, the viewfinder with stabilization turned on is surprisingly jumpy compared to the Nikkor 70-300 f/4.5-5.6 IF ED. I can often not tell the difference (in the viewfinder) between OS on and OS off. It seems that this can be rectified by choosing a different OS mode ("dynamic" or "moderate") with the USB dock. However, to get more viewfinder stabilization, one might have to sacrifice a little bit of in body image stabilization according to a Sigma rep I spoke with over the phone. Note I purchased this lens WITHOUT the Sigma dock, and am thinking of purchasing the latter soon. With the initial shock of jumpy viewfinder stabilization having passed, I am now slowly getting used to the OS on this lens. Despite the jumpiness in viewfinder, my actual images come out quite sharp, even at 1/20-1/10s.
The rep also said that the lens is safe to put on a tripod even although there is no tripod collar. I am deciding between the Nikkor 70-300mm f/4.5-5.6 and this Sigma, and I will probably keep the latter because the extra reach seems quite useful to me. This lens also feels quite a bit heavier than the Nikkor 70-300mm, but the weight makes handling the lens easier than the Nikkor. The lens is also beautifully designed, and I am really appreciating the push-pull mechanism to adjust the focal length. It gives me less arm fatigue than having to turn the focal length ring.
Sigma 100-400 is quiet compared to the Nikkor 70-300, especially while autofocusing and when VR turns on, which may be a bonus when photographing wildlife. However, it does seem that the Nikkor focuses a little bit faster than this Sigma at times. Again, I was told that the AF can also be adjusted with the dock, so perhaps even the AF acquisition can be improved with the dock.
For what it's worth, I am attaching some sample images taken with this lens on a Nikon D500. They were all taken at 400mm, in a not particularly bright environment from my balcony. The shot of the moon is handheld. I don't know if it uploads as a sharp image on Amazon, but it was surprisingly sharp for me!
