Deep Review of Sigma 100-400mm F5-6.3 DG DN OS | Contemporary

Jun 17, 2020
You may want to check out our interesting video of taking this lens on a trip to Tibet and Western China.


Before the release of the Sigma 100-400mm F5-6.3 DG DN OS | Contemporary (hereinafter referred to as: 100-400mm F5-6.3), we were fortunate to get our hands on it and went to Tibet and the western part of Sichuan Province in China for an in-depth test shooting.

Among our telephoto lens, the ones of 70-200mm and 100-400mm are the most commonly used since their larger apertures and longer focal lengths. 70-200mm is suitable for portraits, documentary and etc., and 100-400mm is better for landscape and travel photography. Both have their own strengths and deserve their own unique places.

Today, with the huge development of our technology on cameras, 100-400mm lenses are much easier to use and more of us are getting one. This time we went to Tibet, trying to see what the 100-400mm from Sigma can do. Before the trip, we brought Sony’s FE 70-200mm GM OSS lens for comparation but in the end we always reached for the former. The advantage of a longer focal length is so obvious!

The lens sent to us required an adapter to be mounted onto Panasonic S1 and G95. A little troublesome, but the advantage of its focal length triumphed all. My collogues who only brought the 70-200mm were really envious.



The overall design of the Sigma lens is very shapely. As a new member of the Contemporary series, it is relatively small and portable when contracted, which allows it to be easily carried in various camera bags (such as this semi-professional one from Lowepro, its lower compartment can easily hold our lens).

Due to the ultra-long focal length of 100-400mm, the flexibility that comes with it is self-explanatory. It is a perfect complement for your arsenal of lenses apart from commonly used 24-70mm and 24-105mm.

The zoom ring and focus ring are covered with fine rubber, which is sweat-proof and cold-proof, and it is easy to operate even with gloves.

When it goes to the 400mm end, its length is quite impressive.

Due to its non-constant aperture design (the volume should be much bigger with a constant aperture), the maximum aperture is between F5-6.3. And there is no aperture ring. The actual aperture value after your zooming can be viewed in the camera.
It is worth mentioning that although the max aperture is not quite large, it performed well in various environments with modern digital cameras (which delivers generally excellent image quality with ISO set under 800). Even in the dim forest, handheld shooting is not an issue. In addition, because of the long focal length, even with the maximum aperture of just F6.3 at 400mm, the blur effect is really excellent (samples at the end of the review).

On the side of the lens body, the shiny "C mark" represents its membership of Sigma’s Contemporary series. Beside it is the zoom ring lock, which can avoid maloperation caused by the shift of the lens barrel under gravity.

As a high-quality lightweight telephoto lens, there are multiple dedicated function buttons and dials to meet your needs of fast shooting.

From top to bottom:
AF/MF switch

Choice of focusing distance: FULL (full range)/6m to infinity/﹣6m (within 6m). Thanks to these three settings, you can quickly switch to reduce the focusing time. Such as when shooting far away for flying birds, cutting to 6m-infinity will save the lens motor a big amount of hunting travel.

AFL (auto focus lock button): Press this button after focusing, the focus will be locked, and will no longer automatically focus. Then you can relieve your fingers from half-pressing.

OS button for you to set the image stabilization of the lens to strong, medium and off.
Due to the long zoom-in travel, the rear lens glasses are quite far away from the mounting. Its high-precision and high-strength brass bayonet has 4 fixing screws and a sealing rubber ring. From our testing experience of the trip to Tibet, its waterproof and dustproof capability is fantastic.

Sigma sent us an E-mounted one( though I prefer a L-mounted one).

The lens uses a 9-blade design. After closing the aperture to its minimum, the aperture is rounded enough to produce a nice blur effect.

Main specifications (L-mount)

Lens Construction: 22 elements in 16 groups (1 element for FLD, 4 elements for SLD)
Angle of View (35mm): 24.4°—6.2°
Number of Diaphragm Blades: 9 (circular aperture)
Minimum Aperture: F22-29
Magnifications: 1:4.1 (400mm end)
Minimum Focusing Distance: 112 (100mm end)-160 (400mm end) cm
Filter Size : 67mm
Dimensions(Diameter x Length): 86mm × 197.2mm
Weight: 1135g (including rubber protective ring PT-31)

This lens incorporates fluorite glass (special low-dispersion glass), which not only has strong light transmission, but also effectively suppresses chromatic aberration and better improves the image quality. The front glasses’ multilayer coating is transparent and elegant with the internal structure clearly visible under the light.

As everyone knows, Sigma lenses used a large number of advanced glasses, coupled with aluminum alloy shells for their pursuit of high image quality, and thus they were once called "Workout lenses" in China. But in the previous year, Sigma has developed its own magnesium alloy, so the weight of the lens has dropped significantly. 100-400mm F5-6.3 undoubtedly took that advantage and reduces the weight and facilitates handheld shooting. The rubber ring on the rear lens barrel, which is a good decoration at first glance, covers the connection points for a tripod ring.

Remove the rubber ring, you can install the matching tripod ring. Due to the long lens barrel, attaching the tripod ring and connecting the tripod can change the center of gravity of the system, reduce shakiness and protect the camera mount.

According to Sigma, the matching tripod ring should be TS-111.

The lens construction adopts a design of 22 elements in 16 groups, including one FLD fluorite grade low dispersion lens and four SLD special low dispersion lenses, so goof dispersion correction results can be expected. Although it is a C-series product, Sigma did not scamp work and stint material

Performance Tests

As mentioned before, the 100-400mm F5-6.3 we got is the E-mount version, so we chosed Sony a7RⅣ as the body, which is obviously a test of the camera performance.
The room is clearly not spacious enough.

001 Resolution
We tested three focal lengths with this 100-400mm lens. Let's first look at the image quality performance of each focal length. It should be noted that because of its floating aperture design, the maximum aperture values at three focal lengths of the lens are different.

100mm end’s central and edge resolution
At the 100mm end, the image quality of the center at the maximum aperture of F5 is quite good, but the edge resolution has a significant drop. The image quality has improved after closing down the aperture by one stop. The image quality of the center and corners reached the highest quality with F8, and began to decline in F16, which should be related to the high pixels of the Sony body.

200mm end’s central and edge resolution
At the 200mm end, the center image quality is good at the maximum aperture, but there is a visible decrease in the edge image quality. The aperture is reduced to F8 (actually only a little bit), the sharpness of the picture and the edge image quality is significantly improved. When the aperture is closed to F16, the central image quality and edge image quality begin to decline (and Sony a7RⅣ over High pixels), especially at F22 and F25, the edge image quality has been obviously blurred and softened.

400mm end’s central and edge resolution
With 400mm, the overall image quality is still good. There is no obvious dispersion at the maximum aperture of F6.3. When the aperture is reduced by one step, the center image quality has become very solid, and at the maximum aperture, the edge image quality is also very good. Even at the minimum aperture of F29, the focal length is inevitably affected by the high-pixel body, but the overall image quality is good.
It can be seen that the overall imaging quality of this lens is very good, which can provide enough image quality for everyone.

002 Bokeh
The following picture is the bokeh test for different focal lengths.

Shot with the maximum aperture with 3 focal lengths, there is a small amount of vignette on the edge. But only a small amount of mango-shaped light spots appeared on the edges of the 100mm and 200mm ends. Due to the longer focal length, the depth of field at 400mm is shallower than 100mm and 200mm ends, but the erosion of the vignetting is also more obvious. As can be seen from the 400mm end GIF above, the mango-shaped light spots are closer to the center.
Of course, no matter at which focal length, after closing the aperture by one stop, the light spots in the center and edges become very round.
Due to the 9-blade circular aperture design, it can obtain a beautiful 18 starbursts after closing the aperture smaller. The 100mm and 200mm ends have starbursts at F11, and 400mm focal length end has starbursts at F16.

003 Official MTF
Judging from the official MTF curves, the resolution on both 100mm and 400mm ends is better than many China’s fixed-focus lenses famously known for their quality. And no matter what focal length you are using, the outcome image’s contrast is high enough.

However, this lens’ both ends have their own problems. For example, at 100 mm, the image quality of its edge will see a visible drop, but the blur is still pretty good. At 400mm, the resolution performance is still excellent, but the bokeh performance is slightly under 100mm. In general, this is a lightweight, high-performance product that does not lose its comprehensive performance to many nice primes. And its performance on APS-C machines is also at a high level.

In Sigma's official words, the lens combines the latest technology and optimization for mirrorless systems to achieve uniform high-resolution image quality from the center to the edge. From the wide-angle end to the telephoto end, it can maintain excellent optical performance in various situations and play its true value as a zoom lens.

004 Vignetting

100mm F5


100mm F5.6

100mm F8

100mm F11

100mm F16

100mm F22

200mm F5.6


200mm F8

200mm F11

200mm F16


200mm F22

200mm F25

400mm F6.3


400mm F8

400mm F11

400mm F16

400mm F22

400mm F29

As a telephoto lens, the vignetting control at the 100mm and 200mm ends is not bad. You can basically remove vignetting by closing the aperture by 1-2 stops. The vignetting at the 400mm end is more serious. Since the maximum aperture is F6.3, which is smaller than the maximum aperture of the first two focal lengths, the vignette is not basically eliminated until F11.

005 Distortion


Most telephoto lenses or zoom lenses will have pincushion distortion at the telephoto end. Let's look at the comparison of the shots from three focal lengths (all the internal corrections are turned off during the test). This lens has pincushion distortion at different focal lengths. The 100mm end is more obvious than the 200mm end, and the 400mm end is relatively the most slight. You can turn on the distortion correction function in the machine, or adjust it through the post software.

006 Color Reproduction
We used this lens to shoot the Delta color board (the color mode of the camera body is set as the standard mode), and the color shift results was obtained through the color-adjusting software. As can be seen from the following picture, the overall color reproduction of the lens is quite accurate, but compared to some A series lenses we have tested before, the color saturation is higher and the contrast is stronger.


007 Dispersion
Judging from the enlarged test screenshots, at the maximum aperture, the colors are naturally transited, with no obvious dispersion or glaring, and there is no obvious purple fringing in the high-contrast area around the light source.


008 Minimum Focusing Distance
Shooting at the 400mm end, the foreground doll's magnification is good, and the background blur is also quite natural. The enlarged screenshot shows that the lens has no obvious dispersion at the maximum aperture, and the sharpness of the focal part can meet our close-up needs. Combined with the resolution test, if you close the aperture slightly in real shooting, you can get excellent close-up image quality.


009 Focus Switching Test
After turning on the autofocus of the camera body, we clicked on the screen to make the lens quickly focus on different objects. As you can see from the GIF below, the autofocus performance of this lens is very good, with a quick response, and you can aim and switch focusing points quickly.


010 AF Tracking Test
During the AF tracking test, we did the normal speed and high-speed focusing test. It can be clearly seen from the video below that the lens's tracking and auto focus speeds are very fast. There is no issue of repeatedly searching for the focus point.

011 Focus Breathing Test
It can be seen from the test that during the change of focus, the displacement of the left and right objects is very small, indicating that this lens will perform well when shooting video. Check out the video for full detail.


012 Focus Shift Test
Judging from the focus shift test at the maximum aperture, this lens has a very slight focus shift phenomenon during zooming (the background blur is really good). And you can set a smaller aperture to help with the focus shift.

Actual Shooting Experience

This time we went to West Sichuan to shoot and brought Sony a7RIV and a9 and tons of lenses. 100-400mm and 24-70mm were the only two that we eventually mount on cameras for the most of the time. We shot some time-lapse using a7RIV the first day, but the performance and handling experience was bad. We soon turned to a9 and did not care about shooting 8K.

We also brought a Sony 100-400mm, thinking about doing some comparative tests. As a result, the weight scared me away from taking it for shooting. When you try to shoot on the road, your lenses’ weight might matter the most.

Of course, nothing is perfect. Without a tripod ring, it is quite embarrassing to install and fix it in place. In such a high-altitude place where winds and rains are heavy, shooting at 400mm was no easy job. For safety, two tripods were used to secure the stablization.

In fact, this lens is not very heavy and can be easily fixed with Gitzo’s gimbal.

With Lennon's tripod, the moon shots were taken with no sweat, and the recording of the moon video was also perfect (at this time, the camera body was replaced with a6600). Equivalent to the 600mm focal length of fullframe (If Sigma provided with a 2x teleconverter, it will be perfect). It is totally enough for shooting planes and birds!


Look for the details of the moon.

Of course, another benefit of a telephoto lens is that you can shoot far straight away while the others have to walk much closer.

What's amazing is that the combination of the lens’ stabilization with the Sony camera's gives you high success of shooting a sharp image even handheld. With 1/13’s shutter I managed to get most of the results clear. What a 100-400mm telephoto!

When shooting close with the maximum aperture at 400mm, the magnification effect is good, with very shallow depth of field and full details of the flowers. This should be a pretty good “half-macro lens" for your APS-C body.

It is also competent for portraits. Although 100-400mm is definitely not a dedicated focal length, it can indeed take "clean" portrait photos.

Mountains at 10km away felt close at hand with a 100-400mm lens.

As mentioned before, the lens has excellent focusing performance. In actual use, we used it with high-speed continuous shooting to capture some fast-moving subjects. The focusing experience is really simple and efficient.


It's still easy to take 15 photos and choose one!

When seeing some animals that you might not want to provoke, the advantage of an ultra-telephoto lens is obvious. You can shout away, take your time and your shots calmly and walk away safe and sound.


Sigma 100-400mm F5-6.3 DG DN OS | Contemporary, as an ultra-telephoto zoom lens, is not only relatively lightweight, but also has good image quality. It is also quite good at shooting video. Definitely worth your attention no matter you are a pro or an enthusiast.

What’s good:
1、 Nice image quality
2、Dust-resistant and water-resistant
3、Excellent build quality and styled design
4、Lightweight design with good portability

What to improve:
1、The aperture should be larger
2、Better to include a tripod ring in box

Sample gallery: to the site's limitation of file size, I've uploaded samples shot with this lens here. Please check them out.)