Aberration is an important factor for the lens performance. To actualize a high-performance lens, one of the essential elements is aberration correction. When it comes to aberration, there are chromatic aberration of magnification and axial chromatic aberration. It is possible to correct the chromatic aberration of magnification in photo-editing software whereas axial chromatic aberration cannot be corrected afterwards. This lens incorporates FLD (?F? Low Dispersion) glass elements, which have performance equal to fluorite, and SLD (Special Low Dispersion) glass elements, and by optimizing the power alignment of the lens, both types of aberration have been corrected. The lens achieves ultra-high image quality through the entire focusing range. Also, by appropriate alignment of aspheric lenses, astigmatism and field curvature are corrected. The result is superior optimum resolution even in peripheral areas.
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