In order to combine outstanding wide-aperture, mid-telephoto performance with F1.4 brightness at maximum aperture, this lens incorporates 17 optical elements in 12 groups—an uncommonly large number of elements for a prime lens. By including three FLD glass elements, two SLD glass elements, and one aspherical lens element, the optical system minimizes axial chromatic aberration to deliver extremely high resolution along with ample peripheral light volume. The area in focus is extremely sharp, while the area out of focus features a beautiful bokeh effect with highly natural colors, making this lens a powerful choice for portrait photography. The optical system also minimizes sagittal coma flare, making this lens excellent for capturing starry skies.
Exceptional peripheral brightness
The most effective method of ensuring ample light is to maximize the diameter of the first element of the optical system. With its large filter diameter of 105mm, the SIGMA 105mm F1.4 DG HSM | Art delivers a significantly greater volume of peripheral light than other lenses in its class. Minimizing vignetting while offering a beautiful bokeh effect, this lens is ideal for portrait photography.
Exclusive low-dispersion glass
The degree to which light is refracted by glass depends on the light's wavelength. This fact causes different colors of light to focus at slightly different points. The result is chromatic aberration, the color fringing that is particularly noticeable in telephoto lenses. Most chromatic aberration can be removed by combining a high-refractivity convex lens element with a low-refractivity concave element. Yet residual chromatic aberration known as “secondary spectrum” may still remain. To minimize this secondary spectrum, which can be a serious issue with conventional lenses, SIGMA lenses feature up to three types of exclusive low-dispersion glass offering superior performance: ELD (Extraordinary Low Dispersion), SLD (Special Low Dispersion) and FLD (“F” Low Dispersion). In particular, FLD glass offers ultra-low dispersion in combination with high transmittance and the anomalous dispersion characteristics of fluorite. Meticulous deployment of these types of exclusive low-dispersion glass and optimization of power distribution gives SIGMA lenses superlative image rendition undiminished by residual chromatic aberration.
Designed to minimize flare and ghosting
From an early stage in the lens design process, flare and ghosting have been measured to establish an optical design resistant to strong incident light sources such as backlighting. SIGMA’s Super Multi-Layer Coating reduces flare and ghosting to help photographers produce sharp and high contrast images even in backlit conditions. The included lens hood can be attached to block out extraneous light, which can have a negative effect on rendering performance.
Professional specifications allowing photographers to work in all types of weather
Like SIGMA’s Sports line lenses, the 105mm F1.4 DG HSM | Art features a highly effective dust- and splash-proof structure with special sealing at the mount connection, manual focus ring, zoom ring, and cover connection, allowing photographers to work in all types of weather. In addition, the front of the lens is protected by a water- and oil-repellent coating that makes cleaning easy. The high-speed, high-accuracy autofocus helps photographers react in an instant to get those special shots.
Instead of conventional ABS plastic, the exclusive lens hood features CFRP (carbon fibre reinforced plastic), a light but strong material used in the interior and exterior fittings of aircraft, among many other applications. The removable Arca-Swiss tripod socket is compatible with Arca-Swiss platforms and clamps, and its exclusive protective cover makes the lens easier to carry and use when shooting hand-held.
Fast AF with 'full-time' manual focus
Full-time manual focus function allows the lens to be switched to manual focus simply by rotating the focus ring.
**Note: The operation of full-time MF may vary based on mount type.
The 9-blade rounded diaphragm creates an attractive blur in the out-of-focus areas of the image.
High-precision, rugged brass bayonet mount
The brass mount combines high precision with rugged construction. Its treated surfaces and enhanced strength contribute to the exceptional durability of the lens.