Hands on with new Sigma 35mm and 65mm F2 DG DN | C
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Sigma just added three ‘I-series’ lenses to its Contemporary lineup, in the form of 24mm, 35mm and 65mm primes. Physically somewhat similar to the metal-bodied 45mm F2.8 ‘C’ released alongside the fp, these new primes promise very good performance and light weight when paired with L-mount and Sony E-mount mirrorless interchangeable lens cameras.
We’ve had our hands on the 35mm and 65mm for a few days; read on for pictures, impressions and key specifications.
Sigma 35mm F2 DG DN
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‘A classic reimagined’ is how Sigma describes this lens, which is one of a trio of new ‘I-series’ primes in Sigma’s established ‘Contemporary’ line. The ‘I’ lenses are described as compact, high-quality optics for mirrorless cameras, offering an alternative to the often large, heavy lenses we’ve seen appear for full-frame mirrorless cameras.
Metal construction
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Like the quirky 45mm F2.8, these new ‘Contemporary’ primes are unusual in featuring a metal construction, including the lens hood. Made from ‘precision cut’ aluminum with a brass mount, the 35mm F2 feels like a premium product. However, at 325g (11.5 oz) it remains relatively lightweight, as well as being (by the standards of most modern mirrorless primes) fairly compact.
On a Sony a7R IV, it feels very well-balanced indeed, with its light weight keeping the combination from feeling front-heavy.
Focus and aperture rings
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Knurled focus and aperture rings add to the somewhat retro-inspired design of these new lenses, although both operate of course ‘by wire’. The focus ring is buttery-smooth yet well-damped, and the ‘clicky’ aperture ring is a joy (though it cannot be de-clicked for smooth operation when shooting video).
The accented ‘cut-out’ between the focus ring and aperture ring is cosmetic (it looks like it should be an annular switch but it isn’t) but does provide a little purchase when mounting and dismounting the lens. Unlike the rest of the lens, this ring has a gloss, rather than matte finish, giving it a strange prominence. Both finishes are something of a fingerprint magnet.
Focus speeds aren’t lightning quick, but are more than fast enough for almost any subject you’d be shooting with a 35mm prime. The focus motor is, for all intents and purposes, silent, though you may hear a slight whine or hum if you’re using onboard microphones to record audio while shooting video.
Optical design
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It might be small (only 70mm long, or about 2.7 inches) but the 35mm F2 packs in ten glass elements in nine groups, including one SLD (super low-dispersion) and three molded aspherical elements, all produced in Sigma’s factory in Aizu, Japan. This fairly complex design is optimized for excellent control of chromatic aberrations and field curvature. Sigma also claims very good correction of coma, which is good news for fans of low light, wide-aperture shooting.
9-blade rounded aperture (35mm & 65mm only)
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Speaking of wide-aperture shooting, the 35mm and 65mm ‘C’ primes feature a nine-bladed aperture, with rounded blades to help deliver circular bokeh at a wide apertures (the 24mm has seven blades). The 35mm F2 accepts fairly standard 58mm screw-in filters and the included metal lens cap attaches magnetically.
The back of the metal cap has a felt ring to prevent it scraping the lens, and this is something of a dust trap. The lens comes supplied with a conventional plastic pinch cap, too.
Dust and splash-proof
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Sigma doesn’t make any great claims about the weather-sealing of the new ‘I’ series, but like all three of the new lenses, the 35mm F2’s brass mount is rated as ‘dust and splash-proof’. To that end, a slim rubber gasket around the mount helps keep any dirt or moisture from entering the camera.
The Sigma 35mm F2 DG DN will be available in mid-January for $ 639.
Sigma 65mm F2 DG DN
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The 65mm F2 is physically very similar to the 35mm, but a little heavier (405g/14.3oz compared to 325g/11.5oz) and very slightly longer. Optically it comprises 12 elements in nine groups, including one SLD element and two aspherical elements.
Sigma says the 65mm focal length encourages a greater working distance than a conventional 50mm ‘normal,’ which in turn provides slightly more of a compression effect for the same composition. Its minimum focus distance is 55cm (21.7″)
The front filter ring is larger than that of the 35mm F2, and accepts 62mm screw-in filters.
The Sigma 65mm F2 DG DN will be available in mid-January for $ 699.
Sigma 65mm F2 DG DN
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Like the 35mm, the 65mm comes with both a pinch-fit plastic lens cap and a rather smart magnetic metal one. There’s also a light, ribbed metal hood with a plastic insert with a clip mechanism that provides smooth and secure attachment to the lens itself.
Despite its extra length and weight, it still balances nicely. We used it on some of Sony’s more recent full-frame models, whose larger grips mean the weight is easy to hold. Unlike some recent FF mirrorless lenses, the lens’s weight is pretty evenly distributed along its length: there’s no extreme front element pulling the front of the lens down.
Sigma 24mm F3.5 DG DN
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Third in the new trilogy of primes (and the only one not available to us at the time of writing) is the lightweight (only 225g/8oz) 24mm F3.5 DG DN. Of the three, this lens is the closest in terms of physical design and handling to the existing 45mm F2.8, but unlike that lens, it promises thoroughly-modern, aberration-free imaging, with ‘high resolving power’ across the entire frame at all apertures.
Its 10 element in 8 group optical design includes one SLD element and three aspherical elements, and a minimum focus distance of only 10cm (~4″) works out to an impressive maximum magnification ratio of 1:2.
The Sigma 24mm F3.5 DG DN will be available in mid-January for $ 549.
Articles: Digital Photography Review (dpreview.com)