Tokina AT-X 16-28mm f/2.8 PRO FX Lens
In Summary
RRP: $1,249
Rating
Rating (out of 10):
- Build: 9.0
- Handling: 8.5
- Image quality: 8.8
- Versatility: 8.0
- OVERALL: 8.8
Announced in July 2010, Tokina’s AF 16-28mm f/2.8 AT-X Pro SD FX is the first in a new generation of ultra-wide angle lenses for cameras with 35mm-sized imagers. There’s no point in buying this lens for a camera with an APS-C sized sensor because it’s big and bulky and there are plenty of lighter and cheaper alternatives that are just as fast. Competition is much less in the target market and Tokina’s pricing is lower than for similar lenses from Nikon and Canon. . . [more]
Full Review
Announced in July 2010, Tokina’s AF 16-28mm f/2.8 AT-X Pro SD FX is the first in a new generation of ultra-wide angle lenses for cameras with 35mm-sized imagers. There’s no point in buying this lens for a camera with an APS-C sized sensor because it’s big and bulky and there are plenty of lighter and cheaper alternatives that are just as fast. Competition is much less in the target market and Tokina’s pricing is lower than for similar lenses from Nikon and Canon.
The Tokina AF 16-28mm f/2.8 AT-X Pro SD FX lens
The 16-28mm zoom range provides photographers with a very wide angles of view, particularly at the 16mm setting, which encompasses an angles of just over 107 degrees. It’s great when you want to cover a wide perspective when shooting landscapes and cityscapes and produces interesting distortions in close shots of certain subject types.
Although the zoom range is relatively narrow, this has enabled Tokina to optimise the design of the lens for higher performance. This includes supporting the f/2.8 maximum aperture throughout the zoom range. Limiting the zoom to 28mm makes sense, since this focal length and narrower angles of view are already covered by standard zoom lenses.
The lens is constructed from 15 elements in 13 groups and includes two aspherical elements and three super-low dispersion glass elements to minimise aberrations at all focal lengths. The front element bulges outwards, making it impossible to fit filters, unless you use Cokin-type attachments.
The lack of built-in stabilisation is largely irrelevant, even though neither Canon nor Nikon offers sensor-shift stabilisation in their DSLR bodies. Experienced photographers usually find it easy to hand-hold very wide-angle lenses at relatively slow shutter speeds. The lens is supplied with a large, clip-over lens hood and end caps.
Build and Handling
Tokina lenses are renowned for their build quality and the 16-28mm f/2.8 is no exception. Most of the lens is made from heavy-duty plastics but they are tightly assembled and weatherproof sealing enables it to be seen as ‘pro quality’.
Weighing 950 grams and 133.3 mm in length when fitted to a camera, it’s a substantial handful, although it felt well balanced on the Canon EOS 5D and 5D II bodies we used for our tests. The mounting plate for the lens is solid stainless steel, suggesting an internal frame of the same (or a similar) metal.
A petal-shaped lens hood is built into the front of the lens to protect the bulbous front element. With this built-in hood and the lens mount included, the 16-28mm f/2.8 lens measures just approximately 144 mm in length and has a diameter across the hood of approximately 90 mm.
The supplied lens cap is 37 mm deep and has generous snap-on clips on either side that grip onto the deeper lobes of the lens hood. It can’t be fitted when these clips are orientated with the shallow lobes.
A distinguishing thin gold band encircles the lens just behind the lens hood. Rearwards of this band, the barrel narrows slightly. The 26 mm wide focusing ring is located just behind this section. It has a 23 mm wide rubber grip with five rows of fairly deep, rectangular dimples and is very pleasant to use.
This focusing ring contains a proprietary One-touch Focus Clutch Mechanism that allows users to switch between AF and MF simply by snapping the focus ring forward for AF and back towards the camera to focus manually. It’s a bit clunky to use until you’re accustomed to it and doesn’t match Canon’s full-time manual focusing, which requires no switch to change focusing modes. Marks on the lens barrel just aft of the ring show the AF and MF positions.
Behind the focusing ring is a recessed distance scale that clicks in for manual focusing mode. It has five settings in metres and feet, ranging from 0.28 metres to infinity. The focusing ring moves through roughly a quarter of a turn as you span this range. Focusing and zooming are controlled by moving internal elements so the front element does not rotate and the length of the lens remains constant.
Tokina has introduced a new ‘silent’ DC motor coupled with a new GMR (giant magneto-resistance) AF sensor to control autofocusing. It’s fast and relatively quiet (though not actually silent), particularly when the camera’s viewfinder is used for shot composition but much less effective for shooting with Live View.
The zoom ring is also 26 mm wide and located just aft of the distance scale. Thick, parallel rubber ridges cover roughly 18 mm of its front edge, while four focal length settings (16mm, 20mm, 24mm and 28mm) are stamped on the trailing edge.
These are lined up against a mark on the lens barrel. We found the 20mm and 24mm to be slightly short of the mark, but not enough to bother most users.
Compared with the focusing ring, the zoom ring is relatively stiff, although it moves quite smoothly. Only time and regular usage of the lens could tell whether this stiffness is due to the newness of the lens or other factors.
Performance
We carried out our Imatest tests on this lens using the Canon EOS 5D body, which is the body we use for all assessments of ‘full frame’ lenses. However, to evaluate general functionality, many of the test shots were taken with the lens on an EOS 5D Mark II body, which supports Live View shooting and video recording.
Imatest showed the lens to be a very good performer on the whole, with centre resolution exceeding expectations at most focal length settings between f/3.5 and f/5.6 and edge resolution coming close at around f/4.5 for focal lengths other than 16mm. The graph below showing the results of our tests is based on JPEG files from the EOS 5D.
The sweet spot for this lens is around 20mm at f/4. Edge and corner softness were apparent throughout the 16mm focal length’s aperture range. Diffraction kicked in at around f/8.
Lateral chromatic aberration was in the ‘low’ band throughout the 16mm aperture range and also at wider apertures around 20mm. However it was negligible for all apertures at longer focal lengths, as shown in the graph below, in which the red line marks the border between ‘negligible’ and ‘low’ CA.
As expected, barrel distortion could be seen at the 16mm focal length, although it was less than we expected for such a wide angle of view. By 20mm the distortion was much less visible and it became quite difficult to detect at the 24mm and 28mm focal lengths.
If anything, there was very slight pincushion distortion at 28mm. However, the overall ability of this lens to control distortion is very impressive and makes it ideal for architectural photography, particularly interior shots.
Vignetting was also very low. Although some corner fall-off was visible in shots taken at 16mm f/2.8, this was to be expected considering its aperture. Slight centre darkening could also be seen with these settings. By f/4 vignetting had been all but eliminated and with the 24mm and 28mm focal lengths it was barely noticeable, even at f/2.8. An impressive achievement for such a wide-angle lens.
Flare can be an issue with wide-angle lenses, especially when strong point sources of light, such as the sun, are within or just outside the frame. Fortunately, the review lens handled such conditions surprisingly well and contrast was largely maintained, although some green ghosting could be seen towards the edges of shots throughout the zoom range.
Bokeh is difficult to assess with ultra-wide lenses because very few things are ever totally out-of-focus. However, for very close subjects at f/2.8 with the 28mm focal length, when the background is thrown out of focus, bokeh appears to be very good for this type of lens.
Buy this lens if:
– You want a fast ultra-wide angle zoom lens for a reasonable price.
– You require superior performance and build quality.
Don’t buy this lens if:
– You use a DSLR with an APS-C sized sensor.
– You want to use filters.
– You require a lightweight lens.
– You want to shoot close-ups.
IMATEST GRAPHS
(based on JPEG files from the Canon EOS 5D)
SAMPLE IMAGES
EOS 5D, vignetting at 16mm, f/2.8
EOS 5D, vignetting at 28mm, f/2.8
EOS 5D, rectilinear distortion at 16mm
EOS 5D, rectilinear distortion at 28mm
EOS 5D Mark II, ghosting at 16mm, 1/180 second at f/11, ISO 200
EOS 5D Mark II, ghosting at 28mm, 1/180 second at f/11, ISO 200
EOS 5D, 16mm focal length, 1/250 second at f/8; ISO 200
EOS 5D, 28mm focal length, 1/250 second at f/8; ISO 200
EOS 5D, 16mm focal length, 1/180 second at f/6.7; ISO 200.
EOS 5D, 28mm focal length, 1/125 second at f/5.6; ISO 200.
EOS 5D Mark II, 16mm focal length, 1/60 second at f/11; ISO 200
EOS 5D Mark II, 16mm focal length, 1/90 second at f/11; ISO 200
EOS 5D Mark II, 16mm focal length, 1/15 second at f/11; ISO 640
You’re not inconspicuous when shooting with this lens; EOS 5D Mark II, 28mm focal length, 1/20 second at f/11; ISO 200
5D Mark II, 16mm focal length, 1/45 second at f/3.5; ISO 200
EOS 5D Mark II, 16mm focal length, 1/20 second at f/2.8; ISO 200
EOS 5D Mark II, 16mm focal length, 1/30 second at f/2.8; ISO 200
EOS 5D Mark II, close-up at 16mm focal length, 1/30 second at f/11, ISO 200
EOS 5D Mark II, close-up at 16mm focal length, 1/180 second at f/11, ISO 200.
EOS 5D Mark II, close-up at 28mm focal length, 1/60 second at f/11, ISO 200
Specifications
Picture angle: 107 degrees 11 minutes to 76 degrees 87minutes
Minimum aperture: f/22
Lens construction: 15 elements in 13 groups with 2 aspherical glass elements and 3 SD super-low dispersion glass elements plus multi-layer coatings
Lens mounts: Canon, Nikon with ‘full frame’ FX sized sensors
Diaphragm Blades: 9
Focus drive: Internal DC motor coupled with GMR magnetic AF sensor
Stabilisation: No
Minimum focus: 28 cm
Maximum magnification: 1:5.26
Filter size: n.a.
Dimensions (Diameter x L): 90 x 133.3 mm
Weight: 950 grams