Sigma 60mm f/2.8 DN A Lens Review

Handling and features
Performance
Verdict
Specification

This 60mm lens is currently available to fit both Micro Four Thirds and Sony NEX cameras and costs around £170 and it sports a bright f/2.8 aperture with rounded aperture blades, for pleasing out of focus blur.
On Micro Four Thirds bodies, this lens provides an angle of view equivalent to a 120mm telephoto lens used on a 35mm camera. On Sony NEX cameras, this lens provides a more moderate telephoto view equivalent to a 90mm lens used on a 35mm camera.
This lens retails for around £170, which seems quite inexpensive. We have a Micro Four Thirds compatible version of this lens available for testing and we'll take a close look at how it performs in this review.

This lens falls into Sigma's new 'Art' line of lenses, sporting the new exterior design, finished with a silver 'A' emblem on the lens barrel. Metal has been used for the lens mount and high quality plastics with various smooth textures have been used for the lens barrel construction.  Weighing only 190g and being only 55.5mm long, this lens is the perfect companion to smaller camera bodies, as well as the Panasonic Lumix G3 used for testing.
Focusing is performed internally and the 46mm filter thread does not rotate during use and the lens does not extend as a result, which makes this lens ideal for use with graduated and polarising filters.  Focus speeds are very quick and the large, smooth manual focus ring offers just enough resistance to make applying fine adjustments a pleasure. This lens uses Sigma's linear focusing system, which does not hold the focusing group in place when there is no power to the lens, so a disconcerting rattle can be heard when the lens is tilted when the camera is powered off, or with the lens removed. This is perfectly normal for the type of focusing system used. The minimum focus distance of 50cm is fairly typical for a telephoto lens with this angle of view, if not especially close.

As far as sharpness is concerned, this lens is an excellent performer, with diffraction being the main limiting factor, as is the case with many Micro Four Thirds system lenses. Sharpness is already outstanding in the centre of the frame at f/2.8 and stopping down to f/5.6 results in outstanding clarity across the frame. Stopping down beyond this results in reduced sharpness due to diffraction, although clarity is still very good across the frame at f/11.

Resolution at 60mmThe blue column represents readings from the centre of the picture frame at the various apertures and the green is from the edges. Averaging them out gives the red weighted column.
The scale on the left side is an indication of actual image resolution. The taller the column, the better the lens performance. Simple.
For this review, the lens was tested on a Panasonic Lumix DMC-G3 using Imatest.

Chromatic aberrations are incredibly well controlled at all apertures, peaking at just over 0.5 pixel widths at f/22. This low level should pose few issues, even with large prints and harsh crops from near the edges of the frame.

Chromatic aberration at 60mmChromatic aberration is the lens' inability to focus on the sensor or film all colours of visible light at the same point. Severe chromatic aberration gives a noticeable fringing or a halo effect around sharp edges within the picture. It can be cured in software.
Apochromatic lenses have special lens elements (aspheric, extra-low dispersion etc) to minimize the problem, hence they usually cost more.
For this review, the lens was tested on a Panasonic Lumix DMC-G3 using Imatest.

Falloff of illumination towards the corners of the frame is well controlled. At f/2.8 the corners are only 0.7 stops darker than the image centre and visually uniform illumination is achieved by f/4.
Extremely mild pincushion distortion of 0.368% is present, which shouldn't pose issues in normal shooting. If absolutely straight lines are paramount, the distortion is relatively straightforward to correct as it is uniform across the frame.
A circular lens hood is supplied as standard, and this lens proved itself quite resistant to flare in testing. When shooting into the light, good contrast is retained.
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Sharpness is outstanding across the frame when stopped down to f/5.6 | 1/500 sec | f/5.6 | 60.0 mm | ISO 160
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Good contrast is retained, even when shooting into the light | 1/640 sec | f/2.8 | 60.0 mm | ISO 160
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Closest focus is 50cm from the sensor plane | 1/400 sec | f/2.8 | 60.0 mm | ISO 160
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Even at maximum aperture, sharpness is outstanding in the centre of the frame | 1/1600 sec | f/2.8 | 60.0 mm | ISO 160
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1/1000 sec | f/5.6 | 60.0 mm | ISO 160
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1/320 sec | f/6.3 | 60.0 mm | ISO 160
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1/3200 sec | f/2.8 | 60.0 mm | ISO 160
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1/800 sec | f/2.8 | 60.0 mm | ISO 160
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With this lens retailing for around £170, this lens represents an inexpensive way to pick up a high quality prime lens for your Micro Four Thirds, or Sony NEX system camera.
There is currently no direct equivalent available for either Micro Four Thirds, or Sony NEX cameras. The closest equivalent for the NEX system is Sony's 50mm f/1.8 OSS lens, which is slightly less telephoto and more bulky, but sports a faster f/1.8 maximum aperture and costs around £195.
Olympus offer a 60mm f/2.8 macro lens for Micro Four Thirds, which costs around £370, with this lens offering life size reproduction at its closest focus.
Whether this lens is fitted to A Sony NEX, or Micro Four Thirds camera, the telephoto focal length and fast f/2.8 maximum aperture make this optic a perfectly good lens for portraiture for not a lot of money.
Even though this lens is reasonably inexpensive, Sigma haven't skimped on build or optical quality. It is capable of delivering pin-sharp results from maximum aperture and it is built well enough to be a worthy investment for many years to come.
Outstanding sharpness from maximum aperture
Compact and lightweight
Good build quality
Quick autofocus