Ultra wide-angle lens for Nikon DSLRs explained
The 18-55mm or 18-105mm kit models supplied with most Nikon DSLRs (such as the D3100, D5100 and D7000) have effective zoom ranges of 27-82.5mm and 27-157.5mm respectively.
That's because of the 1.5x crop factor of DX-format Nikon cameras, which have APS-C (Advanced Photo System - Classic) sensors. They're smaller than the full-frame sensors fitted to the D700 or D3x, which are the same size as a frame of 35mm film.
On DX Nikons, an equivalent focal length of 27mm gives reasonably good wide-angle coverage but can be a little limiting.
At the telephoto end, using FX (full-frame) lenses on DX cameras can be a big bonus. The crop factor plays into your hands, turning a 300mm lens into one with an effective focal length of 450mm.
The tables are turned at the wide-angle end, where FX lenses with even the shortest focal lengths lose more than a little something in translation. For example, an 18mm FX lens on a full-frame camera will give an extremely wide angle of view.
But on a DX camera it will only be about 65 degrees from side to side, or 75 degrees from corner to corner.
Zooming in
DX-format ultra-wide lenses generally need to be designed specifically for APS-C cameras, and aren't compatible with full-frame DSLRs. The rear element extends further into the camera, enabling ultra-wide DX zoom lenses to give a typical range of about 10-20mm or 10-24mm.
At 10mm, the effective focal length is 15mm and the angle of view is much more impressive, at 105 degrees on the diagonal.
Zoom lenses are much more popular for ultra-wide shooting on DX cameras, to the extent that ultra-wide prime lenses are almost impossible to find.
However, we've included the Samyang 14mm prime lens. It's the only lens in the group that's designed for full-frame cameras, but still gives an impressively short effective focal length of 21mm on DX cameras. The diagonal angle of view is 114 degrees (FX) or 92 degrees (DX).
Zoom lenses are convenient, and reduce the frequency with which you need to change lenses on your camera. In the ultra-wide DX class, most lenses have a 2x zoom range of 10-20mm, whereas the Nikon and Tamron lead the field with a 2.4x range of 10-24mm.
Most photographers tend to use ultra-wide lenses at or near their widest zoom settings most of the time. However, there's a lot to be said for shooting at 18mm with one of these lenses, in preference to a standard kit zoom lens, because barrel distortion is generally less pronounced.
The majority of ultra-wide lenses on the market have rectilinear optics. This means that if you were to shoot a sheet of paper from head on, its sides should be as straight as possible in the resulting image.
An alternative is a fisheye lens. These have curvilinear optics that produce a pronounced distortion effect. In the same paper test, the sides of the sheet would look as though they were bowing outwards.
Fisheye lenses
There are two types of fisheye lens, circular and diagonal. The former produces a circular image that only fills the central part of the image sensor, whereas diagonal fisheyes project a larger image circle that covers the whole frame.
We've included the Tokina 10-17mm fisheye zoom in this group, which is a diagonal fisheye and gives full coverage on an APS-C sensor throughout its zoom range.
Whether it's rectilinear or curvilinear, any ultra-wide lens is brilliant for exaggerating perspective. Shoot an object or person from close up and the background will appear to fall away at a much greater rate than when you shoot with a standard lens.
You can use this phenomenon to creative effect. For example, you could artistically distort the shape of three-dimensional subjects, or make tall buildings on a skyline appear to lean in towards each other dramatically.
Depth of field
Yet another bonus is that when you're shooting at really short focal lengths, you can get an enormous depth of field, enabling you to keep both close foreground subjects and distant background objects sharp within an image.
For example, if you shoot at 10mm with an aperture of f/11 and manually set the focus distance to its hyperfocal setting of 45cm, everything in the frame will be sharp from just 22.5cm away, all the way to infinity.
When it comes to autofocus, the Nikon lens and all the Sigmas in this group feature ring-type ultrasonic systems. These deliver super-fast, practically silent autofocusing complete with full-time manual override.
By contrast, the Tamron and Tokina lenses use conventional electric motors, which are slower and noisier. The Samyang has no autofocus at all, so focusing is a strictly manual affair.
Key ultra wide-angle lens features
Lens hood
A flower-shaped lens hood comes with most ultra-wide lenses, and is useful for minimising ghosting and flare. In some cases, the hood is built into the lens.
Filter thread
Not all ultra-wide lenses have a thread for attaching filters. They're absent on the Samyang and Tokina 10-17mm ones, and can only be used at the longest zoom on the Sigma 8-16mm lens.
Mounting plate
All the lenses featured in this group have sturdy metal mounting plates, rather than the plastic mounts that are fitted to some cheap lenses.
Autofocus
Ring-type ultrasonic autofocus is best - it offers very fast and near-silent operation, along with full-time manual override.
Zoom range
A bigger zoom range can be a bonus, but for ultra-wide lenses a short minimum focal length is the key factor. About 10mm is ideal.
Focus distance scale
This is an advantage because it enables you to manually set the hyperfocal distance, for maximum depth of field in landscape photography.
Samyang 14mm f/2.8 IF ED UMC
Samyang 14mm f/2.8 IF ED UMC - £280/ $425
At first glance, a prime lens with no autofocus and an aperture ring at its base looks like a dinosaur. Sure enough, you have to set the Samyang's aperture to f/22 for use on Nikon DSLRs, after which apertures are set via the camera. But the lack of autofocus isn't as major a problem as you might think.
With ultra-wide lenses, the focus position isn't critical because the depth of field is so large. Even when depth of field is reduced, when you're shooting close in at the impressively large maximum aperture of f/2.8, you still get focus confirmation by way of the autofocus light in the viewfinder.
Performance
The 14mm focal length is impressive but the effective 21mm on APS-C cameras is less so. In our tests, images were usually overexposed by as much as a full stop (+1EV), requiring hefty amounts of compensation to be dialled in. Disappointingly for a prime lens, barrel distortion is noticeable. Optical quality is pretty good but the Samyang is only worth considering if you're on a tight budget.
Sharpness
Performance is poor at f/2.8, but the Samyang delivers impressive sharpness by f/4, and only really drops off again at f/22.
Lab test at f/8
Sharpness at 14mm: 2239
Fringing
Colour fringing is only noticeable when you're shooting at the largest aperture of f/2.8, at the edges of the frame.
Lab test at f/8
Fringing at 14mm: 0.07
Distortion
For a prime lens, barrel distortion is extreme, and uneven across the frame. We'd have expected better.
Lab test at f/8
Distortion at 14mm: -4.67
Image test verdict
Overall image quality is poor at the largest aperture of f/2.8, but improves between f/4 and f/16, although barrel distortion is disappointing.
Tamron 10-24mm f/3.5-4.5 SP AF
Tamron 10-24mm f/3.5-4.5 SP AF - £370/ $470
Five years ago, the main contenders on the ultra-wide zooms market were the Sigma 10-20mm and Tamron 11-18mm lenses. While the Sigma is still available, Tamron has upped its game with a newer 10-24mm lens that rivals the Nikon in terms of zoom range.
The Tamron is quite light but feels a little flimsy compared with most lenses in this test.
A few luxuries are lacking, such as the way the focus distance scale is only printed on the end of the focus ring, rather than beneath a viewing window. Autofocus is based on a slightly sluggish but fairly quiet conventional motor, so there's no full-time manual focus override available.
Performance
The Tamron frequently overexposes shots at the 10mm end of the zoom range, usually requiring exposure compensation. At a 20mm focal length, exposures are mostly accurate. There's a slight lack of sharpness at the largest apertures, but performance improves between f/8 and f/11. Good results are possible, but watch the exposure settings.
Sharpness
Outright sharpness is best at the crucial ultra-wide focal lengths, and remains consistent throughout the aperture range.
Lab test at f/8
Sharpness at 10mm: 1681
Sharpness at 15mm: 1766
Sharpness at 24mm: 1488
Fringing
Fringing is only slightly noticeable in the 10-15mm zoom range. At longer focal lengths, chromatic errors are negligible.
Lab test at f/8
Fringing at 10mm: 0.33
Fringing at 15mm: 0.35
Fringing at 24mm: 0.96
Distortion
Distortion is well controlled overall, although barrel distortion is clearly visible at the 10mm focal length.
Lab test at f/8
Distortion at 10mm: -3.86
Distortion at 15mm: -0.23
Distortion at 24mm: -0.81
Image test verdict
The Nikon delivers supremely accurate and consistent metering, and acquits itself excellently in all aspects of image quality.
Sigma 10-20mm f/4-5.6 EX DC HSM
Sigma 10-20mm f/4-5.6 EX DC HSM - £430/ $480
One of the first ultra-wide zooms designed for APS-C cameras, Sigma's original 10-20mm has stood the test of time. It might lack the constant aperture of the newer version but it's lighter in weight, has a more typical 77mm filter thread and is £70 easier on the wallet.
Despite its price, the lens boasts ring-type ultrasonic autofocus and comes with Sigma's usual extras, including a flower-shaped lens hood and good-quality carrying pouch. Overall build quality is high, and a match for the bigger, constant-aperture Sigma 10-20mm. Both editions of the lens carry Sigma's 'EX' designation, denoting superior build and optical quality.
Performance
This is one of the sharpest lenses in the group, even at the maximum available apertures of f/4-5.6. There's plenty of image contrast, and autoexposure values are consistently accurate in any light. Some lenses, such as the Samyang, are poor in this respect. Distortions are slightly more noticeable than with Sigma's 10-20mm f/3.5 lens, but it's a great buy at the price.
Sharpness
Sharpness is impressive, even at large apertures, where the lens outperforms Sigma's pricier 10-20mm f/3.5 model.
Lab test at f/8
Sharpness at 10mm: 2402
Sharpness at 14mm: 2430
Sharpness at 20mm: 2124
Fringing
There's quite a lot of fringing towards the image corners at 10mm, especially in the f/8 to f/22 aperture range.
Lab test at f/8
Fringing at 10mm: 0.24
Fringing at 14mm: 0.25
Fringing at 20mm: 0.41
Distortion
Barrel distortion is apparent at 10mm, turning to mild pin-cushion distortion that remains fairly constant from 14 to 20mm.
Lab test at f/8
Distortion at 10mm: -3.06
Distortion at 14mm: 1.11
Distortion at 20mm: 0.979
Image test verdict
Image quality proved impressive in our lab tests, especially for sharpness at large apertures, where it's the best Sigma lens in the group.
Read the full Sigma 10-20mm f/4-5.6 EX DC HSM review
Sigma 10-20mm f/3.5 EX DC HSM
Sigma 10-20mm f/3.5 EX DC HSM - £500/ $650
Unlike Sigma's original 10-20mm zoom, this has a constant aperture of f/3.5, so the top aperture is f/3.5 across the zoom range. This makes it a little more than one stop 'faster' than the f/4-5.6 lens at 20mm, for faster low-light shutter speeds.
The f/3.5 is also 50g heavier, and has a larger front element to let in more light. Most lenses here have a 77mm filter thread, but this Sigma needs larger, pricier 82mm filters.
Performance
Like the other Sigma lenses on test, this one features fast, quiet and accurate ring-type ultrasonic autofocus, complete with full-time manual override. And, as is the case with all but the Samyang and Tamron lenses on test here, the focus distance scale is neatly tucked away beneath a viewing window. All in all, the Sigma feels well engineered to use, with good handling. We found that distortions were particularly well controlled. In our tests, though, sharpness wasn't quite as good as it was with the older Sigma 10-20mm lens, which is also cheaper.
Sharpness
In the wider half of the zoom range, sharpness is only good from f/8 to f/11. It's disappointing at large or small apertures.
Lab test at f/8
Sharpness at 10mm: 1919
Sharpness at 14mm: 1728
Sharpness at 20mm: 1951
Fringing
Chromatic aberration is most noticeable at each end of the zoom range, but is fairly well controlled between 14 and 18mm.
Lab test at f/8
Fringing at 10mm: 0.34
Fringing at 14mm: 0.3
Fringing at 20mm: 0.22
Distortion
Barrel and pin-cushion distortions are only visible at the shortest and longest extremes of the zoom range respectively.
Lab test at f/8
Distortion at 10mm: -2.52
Distortion at 14mm: -0.27
Distortion at 20mm: 0.85
Image test verdict
Sharpness could be better at large and small apertures, especially at ultra-wide focal lengths, but overall image quality is respectable.
Read the full Sigma 10-20mm f/3.5 EX DC HSM review
Tokina 10-17mm f/3.5-4.5 AT-X107 DX
Tokina 10-17mm f/3.5-4.5 AT-X107 DX - £510/ $670
Out on its own, this is the only fisheye zoom available for Nikon cameras. You can go wild with extreme barrel distortion for really funky images, the effect being most pronounced at the 10mm end of the zoom range. As is typical of fisheye lenses, it's considerably smaller than regular ultra-wide zooms, and weighs a mere 350g. The built-in hood doesn't allow filters to be fitted, which would cause massive vignetting. But, as with all Tokina lenses, overall build quality is great.
One benefit of the fisheye effect is that you get a full 180-degree angle of view at the 10mm zoom setting, which drops off to a still considerable 100 degrees at 17mm.
Performance
Despite the conventional motor, autofocus is fast, if a little noisy. It's normally not an issue, because focusing will usually be in the tiny fraction of the range that covers 0.4m to infinity. Shots are often severely overexposed, but image quality is good and, considering that fisheye lenses usually capture a lot of sky, the Tokina's resistance to ghosting and flare is welcome.
Sharpness
Nice and sharp, especially for a fisheye. The Tokina manages to resolve plenty of detail right into the corners of the frame.
Lab test at f/8
Sharpness at 10mm: Not tested
Sharpness at 15mm: Not tested
Sharpness at 17mm: 268
Fringing
Colour fringing can be troublesome where there are high-contrast edges, such a dark branches against a bright sky.
Lab test at f/8
Fringing at 10mm: Not tested
Fringing at 15mm: Not tested
Fringing at 17mm: 0.489
Distortion
As you'd expect from a fisheye lens, distortion is off the scale. It's most pronounced at the 10mm end.
Lab test at f/8
Distortion at 10mm: Not tested
Distortion at 15mm: Not tested
Distortion at 17mm: -15.4
Image test verdict
Image quality is pleasing, but you need to watch out for overexposure. Note that the fisheye design meant we could not test at focal lengths other than 17mm.
Sigma 8-16mm f/4.5-5.6 DC HSM
Sigma 8-16mm f/4.5-5.6 DC HSM - £550/ $700
This is the widest-angle rectilinear lens available. Like all but the Samyang in this group, it's designed specifically for APS-C cameras, on which it has an effective shortest focal length of 12mm. This gives a huge diagonal angle of view of 115mm, enabling you to shoehorn in more of a scene.
Helping to deliver on the extra-wide-angle potential, the lens's front element is particularly bulbous, and the flower-shaped hood is built in. The lens cap fits via a secondary, circular hood, which also contains a 72mm filter thread around its front edge. The upshot is that you can only attach filters at the longest zoom setting, or you'll get extreme vignetting.
Performance
Sharpness is disappointing at the extreme edges of the frame, and at the centre at the largest available apertures. But it's quite acceptable between f/8 and f/16. Barrel distortion is also quite pronounced at the shortest focal length of 8mm, but is well contained in the 12-16mm sector. This is a good buy if you want to go extra large on your viewing angles.
Sharpness
There's a lack of sharpness, especially at the 8mm end of the range, where you need to be between f/8 and f/16 for good results.
Lab test at f/8
Sharpness at 8mm: 1643
Sharpness at 12mm: 1763
Sharpness at 16mm: 1935
Fringing
Performance is reasonable throughout the range. At mid to long focal lengths, fringing diminishes with smaller apertures.
Lab test at f/8
Fringing at 8mm: 0.28
Fringing at 12mm: 0.06
Fringing at 16mm: 0.11
Distortion
Barrel distortion is clearly visible at 8mm, but drops off at 12mm, switching to slight pin-cushion distortion at 16mm.
Lab test at f/8
Distortion at 8mm: 0.28
Distortion at 12mm: 0.06
Distortion at 16mm: 0.11
Image test verdict
The Sigma 8-16mm really pushes the ultra-wide boundaries for a rectilinear lens. Ultimately, image quality is slightly compromised.
Tokina 12-24mm f/4 AT-X124 PRO DX II
Tokina 12-24mm f/4 AT-X124 PRO DX II - £580/ $600
The Nikon-fit version of Tokina's original 12-24mm lens lacked an autofocus motor. So, on bodies that didn't have an internal AF drive, it could only be used in manual focus mode. The updated Mark II edition puts that right with a built-in motor, so autofocus is available with any Nikon body. Other improvements include new multi-coatings that aim to reduce ghosting and flare.
Like the Sigma 10-20mm f/3.5 lens, this has a constant aperture, so the maximum aperture of f/4 is available throughout the zoom range. However, the shortest equivalent focal length on APS-C cameras is 18mm. Most competing lenses offer a 15mm effective focal length.
Performance
Whereas the Samyang, Tamron and Tokina 10-17mm lenses all have a tendency to overexpose images, this lens often underexposes by a third to a half of a stop. Autofocus is fast but noisy, based on an electric motor. There's no full-time manual focus override, but you get a push-pull action for switching between auto and manual focus quickly.
Sharpness
Sharpness at the centre of the frame is particularly good at the largest available apertures down to f/11.
Lab test at f/8
Sharpness at 12mm: 2079
Sharpness at 15mm: 2159
Sharpness at 24mm: 2433
Fringing
Chromatic aberration is well controlled, and fringing is much less evident than with the original lens.
Lab test at f/8
Fringing at 12mm: 0.14
Fringing at 15mm: 0.17
Fringing at 24mm: 0.14
Distortion
Barrel distortion is only modest at the 12mm focal length. There's practically no distortion at 24mm.
Lab test at f/8
Distortion at 12mm: -2.55
Distortion at 15mm: -1.18
Distortion at 24mm: 0.04
Image test verdict
It's quite an expensive lens to buy and lacks a little width in its maximum angle of view. Image quality is good in every respect though.
Nikon 10-24mm f/3.5-4.5G ED AF-S DX
Nikon 10-24mm f/3.5-4.5G ED AF-S DX - £670/ $860
With a zoom range of 10-24mm, equalled only by the Tamron lens, this is a worthy successor to Nikon's older 12-24mm lens. It provides a wider angle of view at its shortest focal length, and build quality feels robust, with silky-smooth zoom and focus rings.
The lens features two ED (Extra-low Dispersion) elements to ensure excellent sharpness and contrast, and the ring-type AF-S autofocus is super-fast and highly accurate.
Performance
The largest available aperture shifts from f/3.5 to f/4.5 as the focal length extends through the zoom range. For an ultra-wide zoom, the Nikon proved remarkably sharp at its largest apertures in our tests, and there was little vignetting, making it great for handheld shooting in dull light.
From low-lit indoor shots to sunny landscapes, the Nikon gives extremely accurate exposures throughout its zoom range. Distortions are a little more noticeable than with some lenses. But, then again, these can be tuned out automatically with Nikon's latest DSLRs.
Sharpness
Outright sharpness is best at the crucial ultra-wide focal lengths, and remains consistent throughout the aperture range.
Lab test at f/8
Sharpness at 10mm: 1681
Sharpness at 15mm: 1766
Sharpness at 24mm: 1488
Fringing
Fringing is only slightly noticeable in the 10-15mm zoom range. At longer focal lengths, chromatic errors are negligible.
Lab test at f/8
Fringing at 10mm: 0.33
Fringing at 15mm: 0.35
Fringing at 24mm: 0.96
Distortion
Distortion is well controlled overall, although barrel distortion is clearly visible at the 10mm focal length.
Lab test at f/8
Distortion at 10mm: -3.86
Distortion at 15mm: -0.23
Distortion at 24mm: -0.81
Image test verdict
The Nikon delivers supremely accurate and consistent metering, and acquits itself excellently in all aspects of image quality.
Read the full Nikon 10-24mm f/3.5-4.5G ED AF-S DX review
Verdict
For reliable, consistent, top-quality results in practically any conditions, the Nikon 10-24mm is a clear winner.
Sharpness is excellent even at the largest aperture, and images have bags of contrast, even when lighting conditions are flat and gloomy. The ring-type AF-S autofocus system is superbly fast, practically inaudible in operation and comes complete with full-time manual focus override.
Build quality is a good match for Nikon's top APS-C cameras, such as the D7000 and D300s, yet the lens still feels well balanced on lightweight bodies such as the D3100.
The only sticking point with the Nikon is that it's by far the most expensive lens in the group. For a more modest outlay, both Sigma 10-20mm lenses offer advanced features, but the older Sigma 10-20mm f/4-5.6 version is particularly good value.
The Tamron 10-24mm is the cheapest zoom lens in the group, but suffered from exposure inconsistencies in our tests and lacks the Sigma lenses' ring-type ultrasonic autofocus.
For maximum wide-angle coverage, the Sigma 8-16mm is a tempting proposition, but image quality isn't quite as good as with the two Sigma 10-20mm lenses. Another alternative is the Tokina 10-17mm fisheye lens, which gives the widest angle of view in the group.
But the fisheye effect is more of an oddity than something that will appeal on a regular basis. At the other end of the scale, the angle of view offered by the Samyang 14mm and Tokina 12-24mm lenses are disappointing, and the Samyang's distortion is pronounced, especially given that it's a prime lens rather than a zoom.
Best ultra wide-angle lens for Nikons
If you've got a bigger budget, the Nikon 10-24mm f/3.5-4.5G AF-S DX ED can't be beaten in terms of image quality.
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