The well-built Sigma 10-20mm f/3.5 EX DC HSM Lens, at review time, is one of only a few lenses in the ultra-wide angle APS-C lens class to have a fixed maximum aperture. While f/3.5 is not what I typically consider wide/fast, the fixed maximum aperture allows a constant wide open aperture exposure setting to be maintained over the full focal length range of the lens. And the ultra-wide angle focal length range is very useful - I recommend a lens from this class to be part of all APS-C (1.6x) DSLR camera kits.
This review is one of a group of ultra-wide angle lens reviews I am creating and follows the Sigma 8-16mm f/4.5-5.6 DC HSM Lens Review and the Tokina 11-16mm f/2.8 AT-X Pro DX Lens Review. Thus, you are going to see many of the same comparisons and information in each of these reviews.
The Sigma 10-20mm f/3.5 EX DC HSM Lens sample picture above was taken with a Canon EOS 60D at 15mm, f/8.
Getting the proper focal length or focal length range is a very important criterion when selecting a lens. And the first attraction to any ultra-wide zoom lens is in fact the ultra-wide focal length range, so let's review what this focal length range looks like. Being a Sigma "DC" (Digital Camera) lens, the Sigma 10-20 f/3.5 has a smaller-than-full-frame image circle designed to work only on APS-C/1.6x/1.5x FOVCF DSLRs. All of the ultra-wide angle lenses compared in this review are the same in regards to this smaller image circle. Thus, the focal lengths shown for all of the lenses below are similar to 1.6x longer focal lengths on a full frame SLR or DSLR. The Sigma's 10-20mm frames like a 16-32mm lens on a full frame DSLR.
Following is an example of the focal length range of this lens. Click on the image below to view a much larger comparison including 4 other ultra-wide angle lenses.
Use the widest focal length you have available in your kit (perhaps 18mm or 24mm) to closely match one or more of the above focal lengths and base your own comparison on that selection. When deciding which focal length range is best for you, consider the lens(es) you already have and how the ultra-wide angle zoom focal length range aligns with it. Also consider which focal length range you need on the lens that is mounted while using this lens (with no lens change required).
In terms of focal length ranges, the focal length numbers mostly tell the difference. 8mm is wider than 10mm and 24mm is longer than 20mm. The Sigma 10-20mm f/3.5 EX DC HSM Lens and its Sigma 10-20mm f/4-5.6 EX DC HSM Lens sibling have the shortest focal length range aside from the Tokina 11-16, but the overall range differences are not great. Like the rest of these focal length ranges, The 10-20mm range will complement 18-something mm lenses very nicely.
Note that the ultra-wide angle zoom lenses are so wide that they are not going to be the ideal general purpose lens for most people - they are still too wide for this purpose - even on the long end.
As I said in the Sigma 8-16mm Lens Review, a beach poison ivy patch as shown above is perhaps the most dangerous subject you want to shoot with an ultra-wide angle zoom lens. These focal lengths take in a very wide angle of view - and subjects must be close to not become a tiny spec in your frame. One of the best ways to use an ultra-wide angle lens is to find a relatively close subject that you want to stand out, to have presence, in relation to the background.
Landscape photographers are of course one group that loves to find a close subject and frame it in a striking, vast, in-focus scene using the deep depth of field these ultra wide angles of view (with narrow apertures of course) give them.
People are the one subject that you will not want to be too close to when shooting at the ultra wide angles as they will appear perspective-distorted. And this means that, unless you are going for the big head/big nose look, group photos and environmental portraits are the type of people pictures this lens is most useful for. And caution is still required for these shots. Any group members closer to the camera than those in the back of the group by any significant distance percentage will appear larger (potentially much larger).
There a many other uses for ultra-wide angle lenses including architecture (especially interiors) and automobile photography. Or you can simply capture a snap shot containing the big picture.
As I said in the review intro, a constant maximum aperture available over the entire range of focal lengths is a great feature. This feature is shared only by the Tokina 11-16mm f/2.8 AT-X Pro DX Lens in this test group.
An f/3.5 aperture is intermediately wide. It will be marginal for stopping low light action, but much better than the f/5.6 apertures found at the max focal length of some of the alternative wide angle lenses. Here is a table that compares the max aperture for these lenses.
|Canon EF-S 10-22mm f/3.5-4.5 USM Lens||10mm||13mm||18mm|
|Sigma 8-16mm f/4.5-5.6 DC HSM Lens||8mm||8mm||13mm|
|Sigma 10-20mm f/3.5 EX DC HSM Lens||10mm|
|Sigma 10-20mm f/4-5.6 EX DC HSM Lens||10mm||11mm||12mm||16mm|
|Tamron 10-24mm f/3.5-4.5 DI II Lens||10mm||14mm||21mm|
|Tokina 11-16mm f/2.8 AT-X Pro DX II Lens||11mm|
|Tokina 11-16mm f/2.8 AT-X Pro DX Lens||11mm|
|Tokina 12-28mm f/4.0 AT-X Pro DX Lens||12mm|
Keep in mind that built-in flash coverage on most DSLRs will not cover most of the focal length range of this lens, so plan on an alternative method of flash lighting/diffusion if planning to use flash with this lens.
With a wide open aperture, the Sigma 10-20mm f/3.5 EX DC HSM Lens is sharp in the center with sharpness degrading to somewhat soft in the frame corners. At f/5.6, the corners improve a noticeable amount - to very nicely sharp. I don't think that you will notice the improvement realized by stopping down beyond f/5.6. From a sharpness perspective, the results are similar over the entire focal length range.
I need to note one exception to this sharpness summary in the retail-purchased Sigma 10-20 f/3.5 I am reviewing. The left side (about 5% of the frame) is softer the the rest of the of the frame - especially from 10-12mm. Even at f/8, the softness is noticeable. I suspect that this issue will be corrected by Sigma service when I send my 10-20 in for repair.
At 10mm, the Sigma 10-20 f/3.5 exhibits a moderate amount of wave/mustache-type barrel distortion (hard to correct). By 14mm, distortion is very well controlled with some pincushion distortion visible from 16-20mm.
Like most APS-C lenses, the Sigma 10-20 f/3.5 shows some peripheral shading on APS-C DSLR bodies at its wide open apertures. Expect 1.6 to 1.8 or so stops of vignetting at f/3.5. Some shading (nearly a stop) will be just-noticeable in the f/8 corners.
The Sigma 10-20 f/3.5 controls flare very well. This is important for a lens this wide as it is easy to get the sun and other bright lights into the frame. Removing flare during post processing can prove very difficult in many situations.
Expect some CA in the corners at all focal lengths with stronger CA at 10mm.
Bokeh (background blur quality) is not easy to discern in a lens this wide - and is not real important for the uses I have for a lens such as this one. In the 10-20mm range, OOF details generally remain tiny, but this 7-aperture-blade lens does not produce especially nice blur quality.
Unless you are using manual focus, focus accuracy is very important to final image quality - and focus accuracy is the biggest problem I have encountered with 3rd party lenses. Good news is that I am finding the Sigma 10-20mm f/3.5 EX DC HSM Lens to perform well in this regard.
The 10-20 f/3.5 HSM (Hypersonic Motor) also focuses quickly and quietly, and internally - without rotating the filter threads. FTM (Full Time Manual) focusing is available and the focus ring does not turn during autofocus.
The raised AF/M switch is easy to reach with the left thumb. The adequately-sized manual focus ring is firm and is very smooth with no play. Focus distances are well marked and displayed in a window. Focus breathing (image changes size when focusing) is not an issue with this lens.
In the short distance focusing category, the Sigma 10-20 f/3.5 turns in average performance for this lens class. None of these lenses will be confused with a macro lens.
|Canon EF-S 10-18mm f/4.5-5.6 IS STM Lens||8.7"||(220mm)||0.15x|
|Canon EF-S 10-22mm f/3.5-4.5 USM Lens||9.4"||(240mm)||0.17x|
|Nikon 10-24mm f/3.5-4.5G AF-S DX Lens||9.5"||(241mm)||0.20x|
|Nikon 12-24mm f/4G AF-S DX Lens||12.0"||(305mm)||0.12x|
|Sigma 8-16mm f/4.5-5.6 DC HSM Lens||9.4"||(239mm)||0.13x|
|Sigma 10-20mm f/3.5 EX DC HSM Lens||9.4"||(240mm)||0.15x|
|Sigma 10-20mm f/4-5.6 EX DC HSM Lens||9.4"||(240mm)||0.15x|
|Tamron 10-24mm f/3.5-4.5 Di II Lens||9.4"||(240mm)||0.20x|
|Tokina 11-16mm f/2.8 AT-X Pro DX II Lens||11.8"||(300mm)||0.09x|
|Tokina 11-16mm f/2.8 AT-X Pro DX Lens||11.8"||(300mm)||0.09x|
|Tokina 12-28mm f/4.0 AT-X Pro DX Lens||9.8"||(250mm)||0.20x|
The .15x MM (Maximum Magnification) value is high enough for a 10mm lens to produce a dramatic perspective.
The rear-positioned (where I like it) zoom ring is adequately sized, has a nice amount of rotation and is smooth with no play or wobble. Zoom ring rotation is in the opposite direction of Canon lenses (the same as Nikon lenses). The Sigma 10-20mm f/3.5 EX DC HSM Lens does change size slightly when zooming, reaching full extension around 10mm, full retraction at 15mm and then extends slightly again at 20mm.
The overall shape of this lens is smooth with slightly smaller ribs on the focus ring than on the zoom ring. The objective end of the lens has a significantly wider diameter than the rest of the lens. I'm not a big fan of Sigma's lens finish (others love it), but the rubber-covered zoom and focus rings consume a significant portion of the lens.
The petal-shaped lens hood is included. Of note that the lens hood on my lens barely locks into place. More than once I've discovered a series of pictures with significant mechanical vignetting caused by the lens hood becoming unlocked and rotating out of position. I like Sigma's center-and-side-pinch lens caps. It is easy to remove the caps even with a lens hood installed.
The Sigma 10-20mm f/3.5 EX DC HSM Lens, like the others in its class, is nicely sized for use. Compare the size and shape of the Sigma 10-20 f/3.5 with some other lenses in its class below. Lenses arranged from short to tall in retracted position, are the:
Sigma 10-20mm f/4-5.6 EX DC HSM Lens
Tamron 10-24mm f/3.5-4.5 DI II Lens
Canon EF-S 10-22mm f/3.5-4.5 USM Lens
Tokina 11-16mm f/2.8 AT-X Pro DX Lens
Sigma 10-20mm f/3.5 EX DC HSM Lens
Sigma 8-16mm f/4.5-5.6 DC HSM Lens
The physical size differences between these lenses are not significant. The same lenses are shown below fully extended with their hoods in place.
Two notables from the image above: The space between the Canon 10-22 and the lenses beside it increases significantly because of its ultra-wide lens hood, and the size order of these lenses practically reverses with the lenses extended and the lens hoods in place. Again, the physical size differences between these lenses are not significant - and all of these lenses have a very nice-to-use size.
|Model||Weight||Dimensions w/o Hood||Filter||Year|
|Canon EF-S 10-18mm f/4.5-5.6 IS STM Lens||8.5 oz||(240g)||2.9 x 2.8"||(74.6 x 72mm)||67mm||2014|
|Canon EF-S 10-22mm f/3.5-4.5 USM Lens||13.6 oz||(385g)||3.3 x 3.5"||(84 x 90mm)||77mm||2004|
|Nikon 10-24mm f/3.5-4.5G AF-S DX Lens||16.2 oz||(460g)||3.2 x 3.4"||(82.5 x 87mm)||77mm||2009|
|Nikon 12-24mm f/4G AF-S DX Lens||16.4 oz||(465g)||3.2 x 3.5"||(82.5 x 90mm)||77mm||2003|
|Sigma 8-16mm f/4.5-5.6 DC HSM Lens||19.6 oz||(555g)||3 x 4.2"||(75 x 105.7mm)||2010|
|Sigma 10-20mm f/3.5 EX DC HSM Lens||18.4 oz||(520g)||3.4 x 3.5"||(87.3 x 88.2mm)||82mm||2010|
|Sigma 10-20mm f/4-5.6 EX DC HSM Lens||16.6 oz||(470g)||3.3 x 3.2"||(83.3 x 81mm)||77mm||2008|
|Tamron 10-24mm f/3.5-4.5 Di II Lens||14.3 oz||(406g)||3.3 x 3.4"||(83.2 x 86.5mm)||77mm||2010|
|Tokina 11-16mm f/2.8 AT-X Pro DX II Lens||19.4 oz||(550g)||3.3 x 3.5"||(84 x 89.2mm)||77mm||2012|
|Tokina 11-16mm f/2.8 AT-X Pro DX Lens||19.8 oz||(560g)||3.3 x 3.5"||(84 x 89.2mm)||77mm|
|Tokina 12-28mm f/4.0 AT-X Pro DX Lens||18.7 oz||(530g)||3.3 x 3.6"||(84 x 90.2mm)||77mm||2013|
For many more comparisons, review the complete Sigma 10-20mm f/3.5 EX DC HSM Lens Specifications using the site's Lens Spec tool. The Sigma 10-20mm f/3.5 EX DC HSM Lens is solidly built and weighs in toward the top of its class - but the weight differences are not that big. The Sigma 10-20 f/3.5 rises above the rest of the class for filter size requirements. 82mm filters are large and relatively expensive, but this size has been growing more common in Canon-mount lenses in recent years.
Be aware that a circular polarizer filter is going to provide very uneven results when used at 10mm on this lens.
For many more comparisons, review the complete Sigma 10-20mm f/3.5 EX DC HSM Lens Specifications using the site's Lens Spec tool.
While comparing these ultra-wide angle lenses, let's take a look at an image quality comparison. Click on the image below to view a 100% crop image quality comparison between 6 ultra-wide angle APS-C format lenses. The comparison loads in a new page. Use Alt-Tab/Ctrl-Tab to switch between pages as you read the commentary below.
Earlier in the Sigma 10-20mm f/3.5 EX DC HSM Lens review, I noted that the specific tested lens performs much worse on the left side of the frame than on the right. This issue is obvious in the above comparisons where the Sigma 10-20mm f/3.5 lands in last or near-last place in all comparison settings (you will see a different performance by this lens in the ISO 12233 chart sample crops). The left side omitted, here are some comparisons.
The Sigma 8-16mm f/4.5-5.6 DC HSM Lens shifts the focal length to the wide end. The Sigma 8-16 has slightly less barrel distortion at 10mm and slightly more pincushion distortion by 16mm. The Sigma 8-16mm has less CA on the wide end, but these two lenses are rather similar in image quality at identical focal length and aperture settings. I'd give the 8-16 a slight image quality edge in the corners. The Sigma 10-20 f/3.5's biggest advantage is a fixed max aperture that holds a 1 to 1 1/3 stop aperture advantage over the shared but again, different, focal length range. The Sigma 8-16mm has a fixed size. The Sigma 10-20 accepts screw-in filters and has a lower price tag.
The Canon EF-S 10-22mm f/3.5-4.5 USM Lens is one of my favorite APS-C lenses. It has slightly less distortion (with less wave distortion at 10mm), has slightly sharper corners, is lighter, does not extend, has a smaller filter diameter (as do all the other lenses in this comparison except the Sigma 8-16 which does not accept screw-in filters) and has a 2mm focal length advantage on the long end. The Sigma 10-20 f/3.5 shows slightly less flare, shows slightly less vignetting at wide open apertures, has the fixed max aperture advantage, has a smaller (and included) lens hood and costs less.
Sigma's 10-20mm f/4-5.6 EX DC Lens is, in practicality, a narrower aperture version of the Sigma 10-20mm f/3.5 EX DC HSM Lens. The f/4-5.6 lens wears a significantly lower price tag - its biggest advantage. The two lenses have very similar image quality at identical settings with the f/3.5 being slightly sharper in the mid-wide focal lengths when both are stopped down. Both lenses have moderately strong barrel distortion on the wide end, but the f/4-5.6 does not have the wave/mustache shaped distortion the f/3.5 has. As expected from a wider aperture lens, the f/3.5 shows less vignetting at the same focal length and aperture settings, though stopped down differences are not significant. The f/3.5 performed better in my flare testing.
The Tamron 10-24mm f/3.5-4.5 DI II Lens is the least expensive lens in this comparisons, but my experience shows that you may not even get what you pay for in this case. My first two copies of the Tamron 10-24 had to be returned for focus calibration issues. Also plagued with poor image quality, the Tamron's advantages are lower cost, slightly lighter weight and an extra 4mm of focal length on the long end.
The Tokina 11-16mm f/2.8 AT-X Pro DX Lens has a significant max aperture advantage over all of the other lenses in this test group. In direct comparison with the Sigma 10-20 f/3.5, the Tokina holds a steady 2/3 stop advantage over the focal length range - and is a better choice for stopping action in low light. But, the Tokina's focal length range is shorter that the Sigma's. The Tokina does not have the wave barrel distortion pattern at the wide end, but these two lenses share similar image quality overall. The Tokina has less vignetting - even stopped down, and the Sigma has less flare. The Tokina does not extend. The Sigma has a closer minimum focus distance and higher maximum magnification.
The Sigma 10-20mm f/3.5 EX DC HSM Lens is available in Canon (reviewed), Nikon, Pentax, Sony/Minolta and Sigma mounts. My standard disclaimer: There are some potential issues with third party lenses. Since Sigma reverse engineers (vs. licenses) manufacturer AF routines, there is always the possibility that a DSLR body might not support a (likely older) third party lens. Sometimes a lens can be made compatible by the manufacturer, sometimes not. There is also the risk of a problem that results in the lens and body manufacturers directing blame at each other. Sigma USA's 4-year warranty is far superior to Canon's standard 1 year warranty (Sigma's international warranty is also 1 year).
The ultra wide angle class of APS-C lenses is one of the harder lens groups to select a best lens for you from. I've liked the Canon EF-S 10-22mm f/3.5-4.5 USM Lens since it became available. The Sigma 8-16mm f/4.5-5.6 DC HSM Lens is also good - I especially like its extremely wide angles of view. The Tokina 11-16mm f/2.8 AT-X Pro DX Lens' f/2.8 aperture is very nice. And the Sigma 10-20mm f/3.5 EX DC HSM Lens is another fine option from the list. My copy of this lens needs serviced for correction of the left-side softness issue, but I do expect Sigma to make this lens right and for this to be a good lens overall. If you don't have an ultra-wide angle lens for your APS-C DSLR, definitely get one - they are very useful pieces of kit.
Review Update: I received my Sigma 10-20 back from Sigma Service. I'm having a very difficult time noticing any improvement in left side sharpness.
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