Leveraging major manufacturing advances at the Aizu factory, SIGMA is now producing ultra-high-precision molded glass aspherical lens elements as large as φ80mm and incorporating them in new products. This premier optical technology promises to set a new standard for excellence in ultra-wide-angle lenses.
Setting a new standard for excellence in ultra-wide-angle lenses
For the Art line, SIGMA began development simultaneously of two ultra-wide-angle lenses offering the key focal length of 14mm: one prime, and one zoom. In 2017, the company launched the 14mm F1.8 DG HSM | Art as the ultimate ultra-wide-angle prime lens. This lens offers outstanding image quality in combination with F1.8 brightness.
Now SIGMA is introducing the 14-24mm F2.8 DG HSM | Art as the ultimate ultra-wide-angle zoom. While minimizing distortion, this lens offers outstanding F2.8 brightness throughout the zoom range and delivers top-level image quality at every focal length and every shooting distance. For these reasons, it is the definitive large-diameter ultra-wide-angle zoom lens.
Outstanding Art line image quality
Designed to team up with 50-megapixel-plus cameras
Designed to team up with 50-megapixel-plus cameras and offer top-level optical performance throughout the zoom range, the 14-24mm F2.8 DG HSM | Art incorporates three FLD glass elements, three SLD glass elements, and three aspherical lens elements, including one large-diameter aspherical element. Effective distribution of these high-refractive-index glass elements further enhances the corrective effect of the FLD and SLD glass. This optical system minimizes transverse chromatic aberration and other optical aberrations, resulting in outstanding high-resolution image quality.
The first element in the optical system is a large-diameter aspherical lens. Optimizing the power distribution of this and the other lens elements minimizes distortion to 1% or lower.* As a result, points of light appear as points without streaking from the center of the image to the edge, and the light volume is also abundant throughout the frame. In addition, simulations performed from the design stage onward have helped minimize flare and ghosting. In combination, these technologies ensure excellent ultra-wide-angle performance.
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.