Overview

The Sigma 20mm F1.4 DG DN Art is a purpose-built mirrorless lens offering outstanding f/1.4 sharpness and excellent image quality, particularly for astrophotography. It improves on its predecessor with weather sealing, a rear filter holder, and 82mm front filters. Build quality is robust with aluminum/TSC materials and a de-clickable aperture ring. However, it is large and heavy, and autofocus can be slow. It suits astrophotographers and landscape shooters seeking top optical performance at a reasonable price.