Sigma I Series Lenses Combine High Performance And Compact Designs

SIGMA IS ADDING to its existing system of DG DN lenses for full-frame mirrorless systems with a brand-new line of compact premium primes called the I series. These lenses – as with all Sigma optical products made in Japan – are designed to complement the more compact and lightweight full-frame mirrorless camera bodies.

There are currently six I series lenses – a 24mm f/2.0, 24mm f/3.5, a 35mm f/2.0, a 45mm f/2.8, a 65mm f/2.0 and a 90mm f/2.8. All four are designated ‘Contemporary’ in Sigma’s organisation of its lens lines. The Contemporary line features compact designs with the latest technologies and superior optical performance.

All the I-series lenses feature durable metal barrel constructions – similar in standard to

Sigma’s heavy-duty cine lenses – with weather sealing. The focusing rings, aperture collars and lens hoods feature a knurled finish for enhanced grip, and special finishes are applied to the exteriors to create a luxurious look and texture. The provision of an aperture collar is designed to enhance useability and they’ve been engineered to give a precise definite action. The optical designs make the most of the size reductions and performance enhancements that are possible thanks to the shorter flange distance of mirrorless cameras compared to DSLRs. Optical performance is also optimised through the use of the latest design and manufacturing techniques for aspherical lenses. Autofocusing is performed via stepper motors to ensure fast, smooth and near-silent operation.

Sigma 24mm f/2.0 DG DN Contemporary

A fast maximum aperture of f/2.0 gives a shallower depth-of-field and allows for more creative scope with selective focusing. Advanced optical design employs both SLD and FLD type elements to effectively reduce chromatic aberrations and optimise sharpness.

Sigma 24mm f/3.5 DG DN Contemporary

This compact wide-angle prime has an optical construction comprising 10 elements in eight groups, which includes one element with super low-dispersion (SLD) characteristics. It also includes three highprecision glass-moulded aspherical elements to optimise corner-to-corner sharpness.

Sigma 35mm f/2.0 DG DN Contemporary

The optical construction comprises 10 elements in nine groups, including one SLD type, three highprecision glass-moulded aspherical types and elements with a high refractive index. Collectively, these special elements correct for axial chromatic and spherical aberrations, sagittal coma and field curvature, ensuring exceptional optical performance even when shooting at the maximum aperture of f/2.0.

Sigma 45mm f/2.8 DG DN Contemporary

The optical design of this compact standard prime creates exceptionally smooth bokeh effects. Spherical aberration is effectively minimised to ensure a gentle transition from the in-focus areas to the soft blur of the out-of-focus effects. This enhances the impression of depth in an image, via the linearly smooth renditions of the foreground and background areas.

Sigma 65mm f/2.0 DG DN Contemporary

The short telephoto focal length and fast maximum aperture provide plenty of scope to utilise selective focusing for creative effect. The optical constructions employs 12 elements in nine groups, including one SLD glass type to effectively minimise axial chromatic aberrations, and two glass-moulded aspherical types to correct for both spherical and comatic aberrations, as well as astigmatism.

Sigma 90mm f/2.8 DG DN Contemporary

The 90mm focal length is a classic, suitable for a wide variety of applications including portraiture. In this compact lens, it’s combined with a bright maximum aperture of f/2.8 and a useful minimum focusing distance of just 50cm. The optical construction is designed to provide a very high level of correction while optimising sharpness across the frame.