135mm F1.8 DG HSM | Art

In addition to an optimized power distribution, this lens features two SLD (Super Low Dispersion) glass elements and two FLD (“F” Low Dispersion) glass elements. These technologies help minimize chromatic aberrations, which tend to appear in the bokeh area outside of focus in portraits, as well as on slender objects such as fine branches. The end result is ultra-high resolution and clarity throughout the image, even at wide-open aperture.

The Art line was launched in 2012 with the SIGMA 35mm F1.4 DG HSM | Art as its first lens. Since then, the line has come to encompass a wide variety of lenses, and the new SIGMA 135mm F1.8 DG HSM｜Art is the line’s sixth large-diameter prime for cameras with full-frame sensors. It sets a new standard for prime lenses in the ultra-high-megapixel era.

To deliver the ultra-high resolution that brings the best out of 50MP or higher ultra-high-megapixel DSLRs, the focus mechanism features SIGMA’s floating system. No matter what the distance from the subject, this lens offers top performance from the center to the edges of the image. By minimizing distortion as well, the lens delivers impeccable image quality—no need for digital adjustment during image processing.

The 135mm focal length delivers a stunning compression effect: even fairly close to the subject, the telephoto ring allows the photographer to establish a variety of dramatic perspectives. The compression effect truly shines in both close-ups and full-length portraits, making composition easy. Moreover, the large diameter with F1.8 brightness makes possible a body shot with an impressive bokeh background. In sum, this lens puts a full menu of compositional options at the photographer’s fingertips.

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.

From the start of the design process, SIGMA measured flare and ghosting to establish an optical design that is resistant to strong incidental light sources such as backlight. At the prototyping stage, SIGMA used not only simulations but actual photographic experiments to assess flare and ghosting under multiple criteria, identify the causes of these issues under a wide range of situations, and take measures to mitigate them. In addition, SIGMA’s Super Multi-Layer Coating helps further reduce flare and ghosting and provide sharp, high-contrast images even in backlit conditions.