CP+ 2018: Hands-on with Sigma 105mm F1.4 Art ‘bokeh master’
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Sigma’s new 105mm F1.4 DG HSM is a beast, weighing in at 1.6 kilos. We’re at the CP+ tradeshow in Yokohama, Japan, where we just got our hands on what Sigma is calling the ‘bokeh master’.
CP+ 2018: Hands-on with Sigma 105mm F1.4 Art ‘bokeh master’
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Even without the hood, the new 105mm is a large lens, with a front filter diameter of 105mm. It’s not particularly long, but as you can see from this shot, which shows the lens mounted on a Canon EOS 6D, it has a very wide diameter of 116mm (4.6 inches). The large tripod ring is included, and can be removed for hand-held shooting.
CP+ 2018: Hands-on with Sigma 105mm F1.4 Art ‘bokeh master’
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With the hood attached, the 105mm gets even larger.
CP+ 2018: Hands-on with Sigma 105mm F1.4 Art ‘bokeh master’
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The new 105mm is unstabilized, which means that the only controls on the lens are an AF/MF switch and a very broad, wide-diameter focus ring. Manual focus is a luxurious experience on all of Sigma’s ‘Art’ series and this lens is no different. Judging purely from our brief experience on the show floor, autofocus speed is similar to the 85mm F1.4: smooth and positive without being as quick and snappy as lenses with fewer pieces of glass to move around.
CP+ 2018: Hands-on with Sigma 105mm F1.4 Art ‘bokeh master’
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And there is a lot of glass inside the 105mm. The new lens comprises 17 elements in 12 groups, including three FLD glass elements, two SLD glass elements, and one aspherical element.
Sigma claims that the lens creates a beautiful bokeh effect, and the well-controlled sagittal coma should make it excellent for capturing ‘starry skies’. A 105mm wouldn’t be our first choice for astrophotography, but we can’t wait to get hold of a shootable sample, and see what it can do.
CP+ 2018: Hands-on with Sigma 105mm F1.4 Art ‘bokeh master’
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Also unveiled at the show was a new macro lens, – a first for the Art range. The 70mm F2.8 DG Macro offers true 1:1 reproduction, and a dust and splash-proof construction.
The lens features an extending, floating, two-group focus mechanism. Optical construction incorporates two FLD glass elements, two SLD glass elements, and one element with ‘a high rate of anomalous partial dispersion and a high index of refraction’. This should minimize axial chromatic aberration. Sigma claims that two aspherical elements ensure ‘razor-sharp’ images at close focusing distances.
CP+ 2018: Hands-on with Sigma 105mm F1.4 Art ‘bokeh master’
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The 70mm macro is a pretty compact short-tele lens when focused at infinity, but gets bigger when the included hood is attached. The front filter diameter is a modest 49mm. Three focus limits can be set, for reducing autofocus ‘hunting’ at short working distances.
CP+ 2018: Hands-on with Sigma 105mm F1.4 Art ‘bokeh master’
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When the lens is racked to its minimum focus distance of 26cm (10.2 inches) the lens itself grows considerably in size (but the hood stays put). Focus is ‘focus by wire’.
At 515g (18 oz) it’s reasonably lightweight, and balances well on our A7R III (with an adapter). We got our hands on a Canon-mount version, but the 70mm F2.8 is also available in Sony FE mount natively.
Articles: Digital Photography Review (dpreview.com)