Sigma 10-18mm F2.8 DC DN Contemporary Lens Review

In general, most photographers consider an ultra-wide-angle zoom lens to be their second or third most important lens, and the Sigma 10-18mm F2.8 DC DN Contemporary Lens is a fantastic choice to fill that slot for APS-C format camera owners.

While the APS-C image circle is huge relative to that of phone cameras, it is small compared to full-frame openings, and this lens greatly benefits from the reduced element size requirements. Though tiny and light, the Sigma 10-18 still features a wide f/2.8 aperture over the entire focal length range, increasing this lens's versatility into low light conditions, and increasing the subject-isolating background blur potential.

This lens is well-designed, nicely constructed, and features a quiet and quick AF system and great image quality, and its affordability will seal the deal for many.

Focal Length Range

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The focal length range is the first aspect to consider for zoom lens selection. Focal length drives subject distance choices, which determine perspective.

The 10-18mm angle of view equates to that provided by a 15-27mm full-frame lens on a full-frame camera, ranging from ultra-wide to moderately wide.

Notably, the 10-18mm range is a precise complement to that of the Sigma 18-50mm F2.8 DC DN Contemporary Lens, and these two lenses are ideal complements to each other in numerous regards.

Often, one cannot back up far enough to get a large subject or vast scene in the frame, and in that case, an ultra-wide angle zoom lens is the right choice. When a foreground subject is to be emphasized, rendered large in relation to a vast background (potentially in sharp focus), moving in close with an ultra-wide angle zoom lens is again the right choice.

What subjects are this ultra-wide angle zoom lens ideal for? Creating that full list is beyond the scope of this review, but let's discuss a few of the genres most photographed by this lens class.

Landscape and nightscape photography is a great answer to that question. It's a big world, and the 10-18mm focal length range is a great choice for capturing the beauty of our planet and beyond. This lens gives us a reason to go out and enjoy the great outdoors. As you may have determined, this lens spent a day with me at Ricketts Glen State Park. It provided the ideal angles of view for this location.

Another genre of photography with huge subjects, often including some landscape, is real estate photography, and this lens is a great exterior and interior focal length range choice for this use. Directly related to real estate photography is architecture photography, and this lens will take in massive structures even when a short working distance is available.

Usually, the structures we photograph are built for people, and people are also a good subject for this focal length range. However, avoid getting too close to people when this lens is mounted.

While a close-up perspective can look amazing in a wide-angle landscape scene, it is generally to be avoided when a person is the primary subject. We do not typically look at a person from really close distances, and if we do, that person becomes uncomfortable with us being in their personal space (and even more so when a camera is in hand). When we look at photos of people captured from close distances, certain body parts (usually the nose) start to look humorously (to some) large.

Unique portrait perspectives can be fun, but this technique quickly becomes overused. Get the telephoto lens out for your tightly framed portraits.

Still, wide-angle focal lengths can be a great choice for photographing people. Simply move back and include people in a larger scene, creating environmental portraits.

The 18mm focal length provides a natural perspective and is a good choice for full-body portraits. The 10-18mm focal length range also works well for small to large groups. Note that group photography requiring an ultra-wide-angle focal length to fit everyone in the frame often leaves those in the front row appearing considerably larger than those in the back row (the subject distance varies by a significant percentage). Back up or move the subjects closer together (front to back) to reduce the multi-row perspective issue.

The 10-18mm focal length range is a great option for the wide work at weddings, family gatherings, and other events, and for photojournalism and sports photography needs. The 18mm end provides especially good general-purpose utility.

This lens, including the focal length range, size, and weight, is an ideal candidate for self-recording (vlogging).

The following images illustrate the 10-18mm focal length range:

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Videographers will find the 10-18mm focal length range equally useful as still photographers.

Max Aperture

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The lower the aperture number, the wider the opening, and the more light the lens can transmit to the imaging sensor. Each "stop" in aperture change (full stop examples: f/2.0, f/2.8, f/4.0) increases or decreases the amount of light by a factor of 2x (a substantial amount).

The additional light provided by wider aperture lenses permits freezing action and handholding the camera in lower light levels and allows lower (less noisy) ISO settings. In addition, increasing the aperture opening provides a shallower DOF (Depth of Field) that creates a stronger, better subject-isolating background blur (at equivalent focal lengths). Often critical is the improved low-light AF performance availed by a wide-aperture lens.

In a 10-18mm lens, f/2.8 is relatively wide. A wide aperture's disadvantages are related to (often significantly) increased lens element size and include larger overall size, heavier weight, and higher cost. Despite the relatively wide aperture, this APS-C format lens maintains the small size, light weight, and lower cost advantages.

Wide apertures are not always required, especially in the ultra-wide-angle focal lengths. Motion blur is caused when subject details cross over imaging sensor pixels during the exposure. Although this lens can be used with a close subject rendered large in the frame, lenses such as this one are often used at normal (or even long) subject distances. The low magnification means those subjects' details more readily stay in their pixels, enabling the longer exposures required to compensate for a narrower aperture to still deliver sharp results, free of subject or camera motion blur.

Also, many uses for this lens require a narrow aperture such as f/8 to keep everything in the frame sharp. Photographers concentrating on landscape, architecture, real estate, etc. may seldom use the widest aperture options in this lens.

Still, f/2.8 remains advantageous for a lens in this class. Those photographing moving subjects, such as at sports events or under the night sky where light levels are so low that the earth's rotation becomes a source of camera motion, usually prefer a wider aperture lens to the increased ISO setting alternatively required.

It is hard to diffusely blur the background with the low magnification provided by an ultra-wide-angle lens. Such lenses render the background details small, keeping the background subjects more recognizable (and potentially distracting). Still, this lens's short minimum focus distance can create a modest blur.

These examples illustrate the maximum blur this lens can create:

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Most will appreciate this lens's constant max aperture, enabling f/2.8 throughout the focal length range.

Image Stabilization

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The Sigma 10-18mm F2.8 DC DN Contemporary Lens does not feature image stabilization. Omitting the optical stabilization system reduces the size, weight, complexity, and cost. However, image stabilization is a useful feature.

Sony addresses that omission with Steady Shot IBIS (In-Body Image Stabilization) in their Alpha cameras. In addition to reducing camera shake, the stabilized imaging sensor provides a still viewfinder image, enabling careful composition. Furthermore, sensor-based AF takes advantage of the stabilized view for improved accuracy.

With no IS switch on the lens, the camera menu must be used to enable or disable IBIS or check the current settings. This extra step is a slight impediment to working quickly, going from tripod mounted to handholding, for example.

Image Quality

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How does the small, light, affordable Sigma 10-18mm F2.8 DC DN Contemporary Lens perform optically? Let's find out.

I usually know how sharp a lens is while performing the resolution chart testing in the lab. This one's sharply focused details were immediately apparent, and the results held up to that expectation.

In the center-of-the-frame wide open at f/2.8, this lens produces sharp images throughout the focal length range. Little or no improvement is seen (or needed) at f/4 in the wider half of the range, and only a slight f/4 improvement is shown in the longer half of the range.

Often, subjects are not placed in the center of a composition. In the periphery of the image circle, where light rays are refracted to a stronger angle than in the center, lenses typically show decreased sharpness. However, this lens holds its great sharpness far into the periphery of the image circle, with only the extreme corners showing modest softness at f/2.8. By f/5.6, even the extreme corners are sharp.

Taking the testing outdoors, we next look at a series of center-of-the-frame 100% resolution crop examples. These images were captured in RAW format using a Sony Alpha 1 and processed in Capture One using the Natural Clarity method. The sharpening amount was set to only "30" on a 0-1000 scale. Note that images from most cameras require some level of sharpening, but too-high sharpness settings are destructive to image details and hide the deficiencies of a lens.

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The 10mm f/2.8 results are excellent. The 14mm and 18mm results would also appear excellent if the f/4 results didn't raise the bar just slightly. Overall, this is great performance.

Next, we'll look at a series of comparisons showing 100% resolution extreme top left corner crops captured and processed identically to the above center-of-the-frame images. The lens was manually focused in the corner of the frame to capture these images.

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Samples taken from the outer extreme of the image circle, full-frame corners, can be counted on to show a lens's weakest performance. Still, the 10mm f/2.8 results are impressive. The 14mm and 18mm f/2.8 extreme corner results are a bit soft (though still good from a relative perspective), and by f/5.6, even the extreme corners are sharp.

When I'm photographing scenes with sharp corners desired, f/8 is likely in use to create enough depth of field for in-focus corner details, and this lens is a great choice for these purposes. Out-of-focus corners are often desired when shooting at wide apertures, and typical wide-aspect ratio videos also avoid using corners. When shooting nightscapes, wide apertures and tack-sharp corners are a requisite.

This lens does not exhibit focus shift, the plane of sharp focus moving forward or backward as the aperture is narrowed (residual spherical aberration or RSA). Many modern lenses automatically correct for focus shift, though focus breathing can create slight angle of view changes.

A lens is expected to show peripheral shading at the widest aperture settings when used on a camera that utilizes its entire image circle. At 10mm f/2.8, expect just under 3 stops of shading in the corners. The amount reduces to just over 2 stops from 12-18mm.

Want less corner shading? Stopping down is the near-universal solution. At 10mm f/4, expect just over 2 stops of shading in the corners. The amount ranges from just under 1.5 stops to just over 1 stop from 12 to 18mm.

F/5.6 brings the last significant vignetting reduction, leaving just over 1.5 stops of shading in the 10mm corners and just over 1 stop in the corners over the rest of the range.

One-stop of shading is often used as the visibility number, though subject details provide a widely varying amount of vignetting discernibility. Vignetting is correctable during post-processing, with increased noise in the brightened areas the penalty, or it can be embraced, using the effect to draw the viewer's eye to the center of the frame. Study the pattern shown in our vignetting test tool to determine how your images will be affected.

Lateral (or transverse) CA (Chromatic Aberration) refers to the unequal magnification of all colors in the spectrum. Lateral CA shows as color fringing along lines of strong contrast running tangential (meridional, right angles to radii), with the mid and especially the periphery of the image circle showing the most significant amount as this is where the most significant difference in the magnification of wavelengths typically exists.

With the right lens profile and software, lateral CA is often easily correctable (often in the camera) by radially shifting the colors to coincide. However, it is always better to avoid this aberration in the first place.

Color misalignment can be seen in the site's image quality tool, but let's also look at a set of worst-case examples. The images below are 100% crops from the extreme top left corner of Sony a1 frames showing diagonal black and white lines.

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There should only be black and white colors in these images, and the additional colors indicate the presence of lateral CA. Most surprising is how little color separation there is for a zoom lens.

A relatively common lens aberration is axial (longitudinal, bokeh) CA, which causes non-coinciding focal planes of the various wavelengths of light. More simply, different colors of light are focused to different depths. Spherical aberration, along with spherochromatism, or a change in the amount of spherical aberration with respect to color (looks quite similar to axial chromatic aberration but is hazier) are other common lens aberrations to observe. Axial CA remains somewhat persistent when stopping down, with the color misalignment effect increasing with defocusing. The spherical aberration color halo shows little size change as the lens is defocused, and stopping down one to two stops generally removes this aberration.

In the real world, lens defects do not exist in isolation, with spherical aberration and spherochromatism generally found, at least to some degree, along with axial CA. These combine to create a less sharp, hazy-appearing image quality at the widest apertures.

The examples below look at the defocused specular highlights' fringing colors in the foreground vs. the background. The lens has introduced any fringing color differences from the neutrally colored subjects.

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There is only minor color separation showing in these results.

Bright light reflecting off lens elements' surfaces may cause flare and ghosting, resulting in reduced contrast and sometimes interesting, usually destructive visual artifacts. The shape, intensity, and position of the flare and ghosting effects in an image are variable, dependent on the position and nature of the light source (or sources), selected aperture, shape of the aperture blades, and quantity and quality of the lens elements and their coatings. Additionally, flare and ghosting can impact AF performance.

This lens produced only minor flare effects even at narrow apertures in our standard sun in the corner of the frame flare test, reflecting excellent performance.

Flare effects can be embraced or avoided, or removal can be attempted. Unfortunately, removal is sometimes challenging, and in some cases, flare effects can destroy image quality. Thus, high flare resistance is a welcomed trait of this lens.

Two lens aberrations are particularly evident in images of stars, mainly because bright points of light against a dark background make them easier to see. Coma occurs when light rays from a point of light spread out from that point instead of being refocused as a point on the sensor. Coma is absent in the center of the frame, gets worse toward the edges/corners, and generally appears as a comet-like or triangular tail of light that can be oriented either away from the center of the frame (external coma) or toward the center of the frame (internal coma). The coma clears as the aperture is narrowed. Astigmatism is seen as points of light spreading into a line, either sagittal (radiating from the center of the image) or meridional (tangential, perpendicular to sagittal). This aberration can produce stars appearing to have wings. Remember that Lateral CA is another aberration apparent in the corners.

The images below are 100% crops taken from the top-left corner of Sony a1 images captured at the widest available aperture.

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While the stars are not perfect dots in these images, these results are quite good from a relative perspective.

This lens produces strong barrel distortion at the wide end, transitions into negligible distortion at about 14mm, and shows modest pincushion distortion at the long end.

While the 10mm distortion is strong, it is not as extreme as we frequently see lens designs produce currently. With increasing frequency, manufacturers are relying on software over physical lens design to manage geometric distortion. Reasons include lower cost, smaller size, lighter weight, reduced complexity, and improved correction of aberrations not software correctable.

Most modern lenses have correction profiles available (including in-camera via lens communication), and the distortion can be corrected using these. Still, geometric distortion correction requires stretching which is detrimental to image quality.

As seen earlier in the review, it is easy to illustrate the strongest blur a lens can create, and wide-angle lenses are inherently disadvantaged in this regard. Due to the infinite number of variables present among available scenes, assessing the blur quality, bokeh, is considerably more challenging. Here are some 100% crop f/11 (for diaphragm blade interaction) examples.

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These results range from not great at 10mm to reasonable at 18mm.

Except for a small number of specialty lenses, the wide aperture bokeh in the frame's corner does not produce round defocused highlights, with these effects taking on a cat's eye shape due to a form of mechanical vignetting. If you look through a tube at an angle, similar to the light reaching the frame's corner, the shape is not round. That is the shape we're looking at here.

These test results are upper-left quadrants reduced in size.

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Strong shape truncation is seen deep in the periphery at 10mm, but the other focal length results are quite good. As the aperture narrows, the entrance pupil size is reduced, and the mechanical vignetting diminishes, making the corner shapes rounder.

A 7-blade count diaphragm will create 14-point sunstars (diffraction spikes) from point light sources captured with a narrow aperture. Generally, the more a lens diaphragm is stopped down, the larger and better shaped the sunstars tend to be. Wide-aperture lenses tend to have an advantage in this regard.

The example above was captured at f/16. The spikes are strong, but the double points on each spike are not my preference.

Aside from the relatively strong geometric distortion and unattractive bokeh at 10mm, the Sigma 10-18mm F2.8 DC DN Contemporary Lens is optically excellent.

Focusing

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The Sigma 10-18mm F2.8 DC DN lens's stepping motor drives fast autofocusing, and low light AF performance is good. AF speed declines in low light, as usual, but this lens can lock focus on reasonable contrast in rather dark conditions.

Focusing is internal, and only faint clicks are heard during AF.

Non-cinema lenses usually require refocusing after a focal length change. As illustrated in the 100% crops below, the reviewed lens does not exhibit parfocal-like characteristics. When focused at 18mm, zooming to wider focal lengths results in focus blur.

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If you adjust the focal length, re-establish focus. This rule usually applies.

This lens has a small, plastic-ribbed focus ring with the same outer diameter as the lens barrel that is not especially easy to tactilely locate. The ring rotates smoothly with ideal resistance.

The manual focus adjustment rate is variable, based on the ring's rotation speed. At 10mm, a full extent focus distance change requires 510° when turning the focus ring slowly. At 18mm, the required rotation increases to 600°. Turn the ring fast, and 220-240° of rotation does the same for the tested focal lengths.

The slow rotation manual focus adjustment steps support high precision focusing.

It is normal for the scene to change size in the frame (sometimes significantly) as the focus is pulled from one extent to the other. This effect is focus breathing, a change in focal length resulting from a change in focus distance. Focus breathing impacts photographers intending to use focus stacking techniques, videographers pulling focus (without movement to camouflage the effect), and anyone critically framing while adjusting focus.

This lens produces a modest change in subject size through a full-extent (worst-case) focus distance adjustment.

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This lens does not have an AF/MF switch. Changing this frequently used camera setting requires use of the menu system (or a switch on some camera models).

The 10-18mm lens has a minimum focus distance of 4.6"(116mm), and at 10mm, it generates a relatively strong 0.25x maximum magnification spec.

Model	Min Focus Distance "(mm)		Max Magnification
Sigma 10-18mm F2.8 DC DN Contemporary Lens	4.6	(116)	0.25x
Sigma 16-28mm F2.8 DG DN Contemporary Lens	9.8	(250)	0.18x
Sigma 18-50mm F2.8 DC DN Contemporary Lens	4.8	(121)	0.36x

At 10mm, a subject measuring approximately 3.1 x 2.1" (79 x 53mm) fills a full-frame imaging sensor at this lens's minimum MF distance. At 18mm, a 4.1 x 2.7" (104 x 69mm) subject does the same.

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The USPS love stamps in the pictures shared above have an image area that measures 1.05 x 0.77" (26.67 x 19.558mm), and the overall individual stamp size is 1.19 x 0.91" (30.226 x 23.114mm).

The minimum focus distance is measured from the imaging sensor plane, with the balance of the camera, lens, and lens hood length taking their space out of the number to create the working distance. At 18mm, there is sufficient working distance at the minimum focus distance, but at 10mm, the plane of sharp focus is only about 0.7" (18mm) in front of the lens without the hood installed. At this distance, the lens shades the subject unless lighting is carefully applied.

10mm minimum focus distance results are sharp in the center, even at f/2.8, but expect the image periphery to be soft, including increased lateral CA. 18mm center-of-the-frame results are a big soft, sharpening quickly as the aperture is stopped down. The periphery remains soft at 18mm, but stopping down brings improvement.

This lens is not compatible with Sigma teleconverters.

Design & Features

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Sigma's Contemporary Lens offers an aesthetically pleasing design with tight tolerances and a quality finish.

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The Sigma 10-18mm F2.8 DC DN Contemporary Lens features a TSC (Thermally Stable Composite) exterior. "TSC is a state-of-the-art polycarbonate that is designed to be both lightweight and extremely durable, and its chemical makeup means it doesn't shrink or expand with changing temperatures. This material is so high-quality that we're also incorporating it into our Art and Sports lenses to provide lightness and thermal consistency." [Sigma]

The 18-50 DC DN extends slightly when zoomed to its shortest focal length, but the full extension is only 0.3" (7.7mm).

This lens's smooth functioning, sharp-rubber-ribbed, slightly raised zoom ring is easy to find and a pleasure to use. I generally prefer a zoom ring positioned behind the focus ring, but in this case, the forward zoom ring position provides a natural grip location for the lens, and the small focus ring is tucked in close to the mount where it stays out of the way.

180° of the area between the rings features molded-in ribs that facilitate grip for mounting and dismounting the lens.

This lens has no buttons or switches. As hinted earlier, the AF/MF button is one I miss the most. Positive is that the lack of switches means increased reliability and decreased opportunity for dirt and moisture penetration.

"Are [Sigma] Contemporary lenses weather sealed? Contemporary lenses feature a gasket at the mount that protects against dust and moisture, but none feature sealing throughout the lens body (this is another reason that Contemporary lenses are more affordable). That said, the vast majority of contaminants work their way into lenses through the rear mount, so as long as they aren’t abused, these lenses will provide many years of trouble-free use, even in moderate weather. For regular use in more extreme conditions, Art or Sports lenses are the way to go." [Sigma]

The small size and light weight make this lens a pleasure to use, including on a gimbal stabilizer.

Model	Weight oz(g)		Dimensions w/o Hood "(mm)		Filter	Year
Sigma 10-18mm F2.8 DC DN Contemporary Lens	9.0	(255)	2.8 x 2.5	(72.0 x 64.0)	67	2023
Sigma 16-28mm F2.8 DG DN Contemporary Lens	15.9	(450)	3.0 x 4.0	(77.2 x 100.6)	72	2022
Sigma 18-50mm F2.8 DC DN Contemporary Lens	10.2	(290)	2.5 x 2.9	(64.5 x 74.5)	55	2017

For many more comparisons, review the complete Sigma 10-18mm F2.8 DC DN Contemporary Lens Specifications using the site's lens specifications tool.

Here is a visual comparison.

Positioned above from left to right are the following lenses:

Sigma 10-18mm F2.8 DC DN Contemporary Lens
Sigma 18-50mm F2.8 DC DN Contemporary Lens
Sigma 16-28mm F2.8 DG DN Contemporary Lens

Observe the size difference in the 16-28mm lens covering similar angles of view with a full-frame image circle. The same lenses are shown below with their hoods in place.

Use the site's product image comparison tool to visually compare the Sigma 10-18mm F2.8 DC DN Contemporary Lens to other lenses.

Like so many other lenses, the 10-18 uses 67mm threaded filters. Standard-thickness circular polarizer filters do not appear to increase peripheral shading, but I still recommend using a slim model such as the Breakthrough Photography X4.

Don't miss the pink insert in the box. When opening a lens box, I move the multi-language paperwork out of the way, retrieve the lens, put all the packaging back in the box, close the box, and put it in the empty box cabinet. I often read the online manual just before completing the lens review. That practice tripped me up this time.

This lens was in my hand before the press release was available (including my otherwise missing hint), and capturing the product photos before non-manufacturer exterior dust becomes applied is always the first review task. I thought I had a defective lens hood. Despite the attachment appearing to be the standard bayonet mount, that method did not work. I managed to press the hood into place for the photos, and then sent an email to my Sigma rep.

That's when I learned that the pink paper was important, and that's when I learned that this lens hood is supposed to be pressed on. Simply align the hood and press it into place, listening for the click. Twist slightly while pulling to remove it.

Sigma shared that an advantage of this design is that it cannot be put on askew, which can cause unwanted vignetting. This plastic petal-style hood design is also compact, yet protective.

After 20 years of using bayonet mount lens hoods, I need to acclimate to the installation change. I haven't decided if I like the new design or not, but this lens and hood are so small that I always leave the hood on.

Price, Value, Compatibility

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Sigma Contemporary lenses always provide good value for their price, and the Sigma 10-18mm F2.8 DC DN Contemporary Lens falls into the same category. This is a relatively low-priced lens that offers great utility.

The "DC" in the name indicates that this lens provides an image circle wide enough to cover (only) an APS-C imaging sensor, and the "DN" indicates that this lens was designed for short-flange mirrorless cameras. The Sigma 10-18mm F2.8 DC DN Contemporary Lens is available in Sony E, Leica L, and Fujifilm X mounts. The "DG" refers to full-frame camera compatibility, and the "DN" indicates that this lens was designed for short-flange mirrorless cameras. The Sigma 10-18mm F2.8 DC DN Contemporary Lens is compatible with all Sony E-mount cameras, including APS-C sensor format models, and it is also available in the L mount (Sigma, Panasonic, Leica).

This lens was made in Japan. Sigma develops, manufactures, and sells lenses based on the specifications of the E-mount, disclosed by Sony Corporation under license agreement.

Sigma provides a 1-year limited warranty, and Sigma Corporation of America provides a limited 3-year warranty extension.

The reviewed Sigma 10-18mm F2.8 DC DN Contemporary Lens was on short-term loan from Sigma Corporation of America.

Summary

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As I said at the beginning of this review, in general, most photographers consider an ultra-wide-angle zoom lens to be their second or third most important lens, and the Sigma 10-18mm F2.8 DC DN Contemporary Lens is a fantastic choice to fill that slot for APS-C format camera owners.

While the APS-C image circle is huge relative to that of phone cameras, it is small compared to full-frame openings, and this lens greatly benefits from the reduced element size requirements. Though tiny and light, the Sigma 10-18 still features a wide f/2.8 aperture over the entire focal length range, increasing this lens's versatility into low light conditions, and increasing the subject-isolating background blur potential.

This lens is well-designed, nicely constructed, and features a quiet and quick AF system and great image quality, and its affordability will seal the deal for many.