Sigma's updated fast 28mm — the f/1.8D ASPH II with improved digital correction for Nikon.
The Sigma 28mm f/1.8 ASPH II is a fast wide-angle prime from Sigma for Nikon F-mount bodies, featuring aspherical optical elements for aberration control. The 'D' suffix in the Nikon variant indicates distance encoding compatibility for 3D matrix metering. The 'II' marking denotes a revised second-generation version.
The lens delivers 28mm at f/1.8 maximum aperture with aspherical correction for reduced coma and spherical aberration at wide apertures, distance encoding for enhanced metering on compatible Nikon bodies, and full-frame coverage. It accepts standard filter threads and provides conventional AF operation.
A fast 28mm prime with aspherical correction was a distinctive offering at its price point, sitting between the more common 24mm and 35mm fast primes in field of view. The f/1.8 maximum aperture enables available-light documentary and street photography in conditions that would challenge slower lenses.
Check autofocus accuracy on modern Nikon bodies — older Sigma AF lenses occasionally exhibit focus calibration discrepancies requiring fine-tune adjustment via the camera body. Inspect the aspherical element coating for any cleaning damage. Test aperture blades for oil contamination, which can cause sluggish operation and affect bokeh rendering.