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ASSESSMENT:
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Optics: *** - ****
mechanical quality: ****
AF function: ***
Price-Performance: ****
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Overall rating: *** - **** (final rounded up to ****)
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GENERAL:
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The Sigma 10-20mm / 3.5 EX DC HSM is an ultra wide-angle zoom for system cameras with an APS-C sensor, Nikon's DX this sensor size. On cameras with small image sensors - often referred to incorrectly as "full-frame" - function lenses for APS-C / DX sensors not or not fully satisfying, because the illuminated image circle is too small for. The Sigma 10-20mm / 3.5 has so far proved in different situations as an excellent ultra wide-angle zoom, require the photos little fiddling with software and also get along z. T. without such. So it's a lens in which you have to take almost no compromise.
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POSITIVE:
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Positive falls first of all on the very decent for an ultra-wide angle zoom range. It ranges from 10mm (110 ° angle) to 20 mm (56 ° angle).
Materials and workmanship are at very high levels. Zoom and focus ring run sufficiently attenuated and without much resistance.
Sharpness, resolution and contrast values in the center are excellent even with the prestigious Nikon D7100. Even at full aperture, there is in the center sharpness is technically nothing to complain about, stopping down to at least 5.6, better 8 or 11 brings even an increase.
The tendency to edge blurring is relatively low even at maximum aperture, although certainly not the word of choice is "knackscharf" that comes to the image quality at the edges. Dimmed things look then a different matter; Aperture 5.6 brings a visible increase in sharpness, from f / 8 or f / 11 will then's really sharp right into the corners.
The susceptibility to flare (absorbed. Lens flares) in direct contrast or strong side light persists, despite the large arched front lens within limits, which is a pleasant surprise. Nevertheless, the use of the lens hood is strongly recommended, and not least because this piece of plastic also represents a degree of protection against mechanical damage of the front lens.
The light intensity is consistent with 3.5 on the right for Ultra wide-angle lenses level.
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NEUTRAL:
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That there is no FTM focus - FTM represents "full-time manual" and means that the photographer having to switch at any time without explicitly on the lens auto focus (AF) to manual focus (MF), intervene in the focus and can track the focus manually - not overly interfere with a lens with such a large depth of field as the Sigma 10-20mm / 3.5.
Distortion is - except for the area between 10-12mm - well corrected quite moderate and via software.
The Sigma 10-20mm / 3.5 vignetting quite strong, z. T. by more than one exposure value at maximum aperture. However, it can reduce the vignetting by stopping down and correct problems in image processing. Stopped down to f / 5.6, it is better at f / 8 and f / 11, it is not a problem.
Chromatic aberration (CA) are in place, but not very strong and easily correctable by the software.
An optical stabilizer is absent and in this focal length range m. E. dispensable, since such a stabilizer price, weight and dimensions would drive up.
The autofocus is very fast and accurate in bright light, in low light, it takes longer but an idea until it finds its target.
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NEGATIVE:
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To complain I actually only that there is no weather protection for these Sigma-Line, the front lens and bayonet against the ingress of dust and moisture protection. When it rains, so you should, even if one has a sealed against dust and splash camera body, without taking pictures with the Sigma 10-20mm / 3.5. Now Sigma not applying this lens although with a dust and weather protection, but it is negative for the photographer in very practical point of view, that such a lack protection. In the final vote I let this aspect of course not be included precisely because Sigma promises no dust and weather protection for this lens.
That the filter size for Sigma 10-20mm / 3.5 very lush with 82mm fails and filters for this ultra wide-angle lens so that a relatively expensive matter, interferes in practice very little, except perhaps for an ND filter (neutral density or gray or Grauverlauffilter) you need for an ultra wide-angle actually no filter. Circular polarization filters are namely ultra wide angle lens is not very useful because they cause reduction of reflections on non-metallic surfaces such as water or glass practically only in the center effectively and improve the contrast, unfortunately, the z. T. clearly visible vignetting even more emphasized.
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COMPARISON:
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In direct comparison, the Sigma 10-20mm / 3.5 EX DC HSM is less than 100 more expensive than the Tamron 10-24mm / 3.5-4.5, but cuts in all areas significantly better (see my 2-star review of the ultra wide-angle lens from Tamron ). The similarly expensive Tokina AT-X 11-16mm / 2.8 Pro DX II towards offering a wider focal length range, but it has the Tokina the consistently higher light intensity on. In the image quality both lenses do not take much; the Tokina is perhaps a trace sharper and more defined at the center, but falls to the edges more sharply and is also somewhat more susceptible to flare (lens flares). Not I can consider here the newly published Tokina AT-X 11-20mm / 2.8 Pro DX Nikkor 10-24mm DX and the Nikon / 3.5-4.5G, which is the only ultra wide angle for APS-C / DX sensors even a weather protection provides against moisture and dust. The reason why I do not consider both lenses is well founded in the price because with about 720 blow both lenses my budget considerably.
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CONCLUSION:
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The Sigma 10-20mm / 3.5 EX DC HSM is a very good in terms of image quality ultra wide angle and is aimed at amateur photographers who wish to make any painful compromises in terms of optical quality, materials and workmanship and is therefore rated 4 stars properly. For the Sigma 10-20mm / 3.5 I speak without reservations from a buy rating. NGC. Tamron 10-24mm the / 3.5-4.5, which I am happy separated again after a short time, the Sigma 10-20mm is / 3.5 to my Nikon DX cameras probably a similar "successful career" as a "lens First Class" as imminent also the Sigma 17-50mm / 2.8 EX DC OS HSM as standard and the AF-S Nikkor 70-300mm / 4.5-5.6G IF-ED VR as a telephoto zoom.
