Panasonic LUMIX G 20mm f1.7 and 20mm f1.7 II ASPH lens reviews: Has Panasonic improved its classic standard prime?By Kevin Carter - Thursday November 07 2013 Lens Review
Panasonic Lumix G 20mm F1.7 II ASPH vs Panasonic Lumix G 20mm F1.7 ASPH vs Panasonic Leica Summilux DG 25mm F1.4
Slight differences in performance arise between the two 20mm models
Compared to its predecessor the new lens should perform similarly, but we measured some slight variation in optical quality. The new model has a slight loss of sharpness in the corners and edges over the previous iteration. Sharpness in the outer field doesn’t quite match the original even when stopped down.
Against the brighter Leica 25mm, the new model has similar levels of sharpness overall but lacks the consistent, edge-to-edge sharpness of that lens when stopped down.
Chromatic aberration is lower but that’s expected to a degree.