This beast of a prime boasts the longest focal length in Sigma’s Art f/1.4 series, but is it a portrait photographer’s dream lens? Michael Topham finds out
Sigma 105mm f/1.4 DG HSM review: Features
If you think Sigma’s 85mm f/1.4 Art DG HSM is big and heavy, this lens is a monster by comparison. It’s not unusual for Sigma’s Art lenses to be heavier than its rivals, but this optic goes further and then some. Compared to Nikon’s AF-S 105mm f/1.4E ED, which protrudes 106mm from the camera body and weighs 985g, this optic measures 131.5mm in length and weighs a hefty 1.65kg.
Part and parcel of its size and weight comes down to its complex optical design that sees 17 elements arranged in 12 groups – an uncommonly large number of elements for a prime lens. The grouping of three FLD glass elements, two SLD glass elements and one aspherical lens element is claimed to minimise chromatic aberration and deliver the highest resolution possible.
If it performs as well as other Sigma primes I’ve tested in the past with low-dispersion glass, I expect to resolve an excellent level of sharpness that’s undiminished by noticeable fringes of colour along high contrast edges.
In typical Sigma fashion, the lens features the manufacturer’s Super Multi-Layer Coatings to prevent flare and ghosting from causing issues when shooting directly towards the light. It’s also equipped with the company’s Hyper Sonic Motor (HSM), which performs autofocus duties and enables full-time manual focusing – a process whereby users can adjust focus manually at any time without being forced to flick the AF/MF switch to manual first.
The lens’s nine-bladed aperture diaphragm offers settings from f/1.4 to f/16. Used at its maximum aperture of f/1.4, these nine aperture blades are designed to create a very attractive rendition to out-of-focus backgrounds, with pleasing spherical bokeh in the highlights, hence its nickname the ‘bokeh master’.
Other features include a minimum focusing distance of 100cm and its compatibility with Sigma’s USB docking device that allows users to update lens firmware and perform various types of customisation and adjustment using Sigma’s company’s Optimization Pro software.
The good news for Sony E-mount users interested in this lens is that Sigma’s MC-11 mount converter is no longer required. The E-mount version performs the same exact functions as the converter, including in-camera lens aberration correction. In addition, the lens is compatible with Sony’s continuous AF (AF-C) and Eye AF functions, which were not previously addressed by the MC-11.
As well as the above, the lens is eligible for Sigma’s mount conversion service. The beauty of this is that if you later decide to switch systems, you can convert the lens to make it compatible with your new camera, which is a far cheaper solution to buying the lens again from new.