SIGMA 150-600/5-6.3 DG OS HSM Sports for CANON

This lens incorporates 2 FLD (“F” Low Dispersion) glass elements, which have performance equal to fluorite and 3 SLD (Special Low Dispersion) glass elements, and compensates for color aberration at the utmost. Chromatic aberration in particular, which could be visible especially towards the telephoto end even when stopped down, is corrected by the optimized design of glass elements including FLD lenses.
* FLD glass is the highest level low dispersion glass available with extremely high light transmission. This optical glass has a performance equal to fluorite glass which has a low refractive index and low dispersion compared to current optical glass. It also benefits from high anomalous dispersion. These characteristics give excellent correction for residual chromatic aberration (secondary spectrum) which cannot be corrected by ordinary optical glass and ensures high definition and high contrast images.

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 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 9-blade diaphragm helps produce an attractive bokeh effect – even at large-aperture settings.