Sigma 100-400mm f/5-6.3 DG OS HSM | Contemporary Lens Review


Martin Benadie


Sigma 100-400mm f/5-6.3 DG OS HSM | Contemporary Lens Review




An African safari is a once-in-a-lifetime trip for many. Capturing memorable images on such a holiday also luckily does not have to cost as much as the trip itself or weigh down your hand luggage with bulky camera gear. For those shooting SLR cameras, I recently had the opportunity to use Sigma’s latest 100-400mm variable aperture zoom lens and was suitably impressed – both on pricing and weight – but also on where it matters most, namely image quality. A safari lens seriously worth consideration – with a few caveats.


Intended Users


For travel, nature, wildlife and bird photography, as well as some macro usage. If your photography falls into these realms and you need a versatile, compact, and lightweight telephoto lens, then this may be the one to strongly consider.


Purple-crested Turaco | The lens is very capable of capturing quality images of trickier subjects like birds.


Build Quality


This lens feels well-constructed. Sigma uses Thermally Stable Composite (TSC) materials along with metals in the design. While there is some plastic feel to the lens, the quality finish gives it a nice touch. This lens is not weather-sealed, but it does have a dust- and splash-proof mount with a rear gasket seal, however. The front and rear elements of this lens also have a repellent coating which makes cleaning easier.


Image Quality


Excellent sharpness. The maximum aperture is a variable one, ranging from f/5 to f/6.3 through the focal range. The 100-400 C is sharp wide open and there is little differentiation between focal lengths aside from 400mm results being very slightly softer than the wider options. What was also interesting was that mid-frame and corner performance nearly matches centre sharpness.


The optics feature four special low dispersion elements to reduce colour fringing and chromatic aberrations paired with a super multi-coating to minimize lens flare. I noted some vignetting when shot wide open but not significant and chromatic aberration is low.


This lens bokeh, referring to the quality of the out-of-focus areas of the image, was also acceptable to me creating nice subject isolation. The rounded 9-blade aperture creates well-rounded specular highlights, the outer transition not harsh with smooth centres.




The 100-400C comes with three options for focusing: auto-focus, manual override, and manual focus. The hypersonic motor did well while using autofocus with decent accuracy overall.


In low light, this lens tends to hunt for focus a significant amount, but that behaviour is not unexpected with slower telephoto lenses. To (potentially) reduce autofocus hunting, autofocus distances can be restricted using the focus range limit switch.


With the optional (and recommended) Sigma USB Dock, the AF system is very customizable. The Sigma Dock allows focus calibration adjustments to be made at 4 focal lengths for 4 focus distances (16 total adjustments).


The dock, working in conjunction with the Sigma Optimization Pro software, allows the lens firmware to be updated as well.


Overall, the HSM-equipped (hypersonic motor) Sigma 100-400mm zoom lens delivers pretty impressive autofocus performance. Over my test period this lens proved to have reliably accurate autofocus performance, even at 400mm and when shooting from close distances.


Image Stabilisation


Using Sigma’s optical stabiliser, I would say you can achieve two or three stops of equivalent stability. At 400mm, I was getting usable images at 1/40th of a second on stationary bird subjects. Mode I (normal) and II (panning mode) are provided via a switch.


Aardvark | I could even capture this tricky aardvark image in very challenging light conditions at a far distance. May not win awards but could at least capture a memorable sighting!


Further compatibility via the Sigma dock:


Dynamic View Mode – This mode offers a recognisable OS effect to the image in the viewfinder. This helps to ensure the composition of images quickly.


Standard Mode – This is the default setting. The OS effect is well-balanced and suitable for various scenes.


Moderate View Mode – This mode offers an excellent compensation of camera shake, and achieves very smooth transition of the image in the viewfinder. The composition of the image remains natural even when the angle of view keeps changing.


I did struggle a bit to attain acceptable shutter speeds in lower light periods of the day owing to the f/6.3 aperture (shooting with a Nikon D7000). This will be less of an issue with a FX (fullframe) body as you will be able to increase your ISO to negate this. This lens is thus not an ideal choice for capturing low light action. Again, one needs to remember the price point of this lens!




Excellent sharpness and image quality in a compact and lightweight telephoto lens. Sigma has definitely captured my attention with their new ART, CONTEMPORARY AND SPORT series of lenses, and this 100-400C certainly adds clout to their starting line-up in this regard. This is lens you will always have with you and brings fun back into your photography. The excellent image quality across the zoom range combined with the price will be compelling for many considering this lens gives photographers more shooting options.


Overall, this lens can deliver a lot of detail under the right conditions. One has to bear in mind that it can be a bit slow in terms of maximum aperture and AF speeds can be sluggish in low light. Personally, I was able to capture some great bird, wildlife and close-up images over my time using this lens. Wildlife photography is one of the best uses for the 100-400mm focal length range and the new Sigma 100-400C does a very capable job in this regard.



  • Weight: 1160g
  • Dimensions w/o hood: 86.4 (diameter) x 182.3mm (length)
  • Filter size: 67mm
  • Push/Pull and twist zoom mechanisms; I found the push-pull workied quite well
  • Rounded aperture diaphragm with f/5 to f/22 range
  • 21 elements in 15 groups, including 4 SLD (Special Low Dispersion) elements
  • Close focus distance of 160 centimetres for a maximum magnification ratio of 0.26x (1:3.8), so can also work pretty well as a macro lens
  • Not included and not optionally available for the 100-400 C is a tripod ring; light weight is obviously a priority for this lens and intention is probably for users to mostly use lens hand-held

Let’s plan your next journey


When we say we’re there every step of the way, we mean it, literally. From planning the perfect circuit, to private inter-camp transfers on Wilderness Air, and easing you through Customs. We’re with you on the ground, at your side, 24-7, from start to finish. Ready to take the road less travelled? Contact our Travel Designers to plan an unforgettable journey.