Handling and features
Performance
Verdict
Specification
This standard lens for APS-C format cameras sports a fast f/1.4 maximum aperture and silent rear focusing with full time manual override. It is available to fit Canon, Nikon and Sigma cameras and costs around £260.
Sigma 30mm f/1.4 DC HSM A Handling and features
With a weight of only 435g, this lens is quite lightweight, especially when the solid build with a brass lens mount is taken into consideration. As a result the lens makes a perfect companion for the Canon EOS 600D used for testing. The lens is finished with a metallic glossy finish in parts, which reinforces the quality feel of the lens.
A silent HSM focusing motor powers the focusing mechanism, which is very quick to confirm focus. However, with the test camera, this lens struggled to focus consistently using phase-detect autofocus, so contrast detection and live view was required during testing to ensure accurate focusing at fast apertures. We tested two samples of the lens, and corrected the focusing issues using the Sigma USB Dock. Focusing is performed by moving the rear group of elements, so the 62mm filter thread does not rotate, making this lens ideal for use with polarising and graduated filters.
Full time manual focus can be applied by simply adjusting the focus ring at any time. Manual focusing is a pleasure as the focus ring is quite heavily damped, and very smooth to operate. Closet focusing is 30cm from the sensor plane, which is typical for a lens of this type.
Sigma 30mm f/1.4 DC HSM A Performance
At maximum aperture, sharpness in the centre of the frame is already very good. Clarity towards the edges of the frame is fair at maximum aperture, but this improves as the lens is stopped down. By f/4 clarity towards the edges of the frame reaches good levels, and very good levels of sharpness are realised towards the edges with the lens stopped down to f/8. Sharpness in the centre of the frame is very high throughout the aperture range, exceeding excellent levels when stopped down to f/2.8 or beyond.
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How to read our chartsThe 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 Canon EOS 600D using Imatest. |
Chromatic aberrations are reasonably well controlled, exceeding three quarters of a pixel-width towards the edges of the frame at maximum aperture, although this level decreases as the lens is stopped down.
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How to read our chartsChromatic 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 Canon EOS 600D using Imatest. |
Falloff of illumination towards the corners of the frame isn't as severe as you may expect from a lens with a fast f/1.4 maximum aperture. At f/1.4 the corners are only 1.03 stops darker than the image centre and illumination is visually uniform with the lens stopped down to f/4 or beyond.
Only a very slight amount of barrel distortion is present in images taken with this lens. Imatest detected 0.467% barrel distortion, which will be barely noticeable, even if straight lines run parallel to the edges of the frame.
A deep circular hood is supplied with this lens, which does an excellent job of shielding the lens from extraneous light that may cause loss of contrast or flare. Even when shooting into the light, contrast remains high.
Value for Money
Priced at around £260, this lens is fairly priced as you get a fast f/1.4 aperture and excellent build quality. Owners of Canon cameras equipped with an APS-C sized sensor may be particularly interested in this lens, as Canon offer no alternative.
Nikon's 35mm f/1.8 DX lens is cheaper at around £150, but the maximum aperture is slower. Whether the slight extra light gathering ability of the Sigma lens is worth just over £100 will be down to you.
Sigma 30mm f/1.4 DC HSM A Verdict
During this test, we did have issues with inaccurate focusing, which may be down to a flaw with the samples provided for review, and were able to resolve using the Sigma USB Dock. Presuming this problem isn't widespread, then this lens is a great choice for owners of Canon cameras, after a high quality, standard lens with a fast maximum aperture. As Nikon users already have the 35mm f/1.8 as a choice, this Sigma lens would probably need to be a little cheaper in order to tempt people away from the Nikon optic.
The Sigma 30mm has a fast f/1.4 aperture and very good sharpness in the centre.