The Sigma 60mm DN lens has been designed specifically for mirrorless cameras with optimal optical arrangement for digital sensors. The A Series denotes Sigma’s new Art range which focuses on quality and creative potential rather than a feature count. Sigma’s new testing equipment ensures fantastic quality to realise that potential. As well as this, the lens uses SLD (Special Low Dispersion) glass for extremely low levels of aberration from the centre, right to the edges of the frame.
The 60mm lens gives an equivalent focal length of 120mm when used on a Micro Four Thirds (MFT) camera, giving a pleasing perspective for portraits. Additionally any defocused areas will have a natural softness (“bokeh”) due to the rounded diaphragm.
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.
When photographing with point light sources such as electric lights or reflections on a body of water in the background, the rounded 7-blade diaphragm helps produce an attractive bokeh effect—even at large aperture settings.
Linear AF motor
This lens benefits from a linear AF motor which moves the lens unit directly without the need for gears or other extra mechanical parts. This system ensures accurate and quiet autofocusing, making the lens excellent for both recording video and taking still photos.
High-precision, rugged brass bayonet mount
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. The brass mount combines high precision with rugged construction. Its treated surfaces and enhanced strength contribute to the exceptional durability of the lens.