Overview

The Panasonic Leica 100-400mm f/4-6.3 ASPH offers impressive sharpness, especially at wider focal lengths, though at 400mm resolution is weaker until stopped down to f/8. It controls chromatic aberration well and has pleasant bokeh, but flare can be an issue. Build quality is excellent with an all-metal, weather-sealed body, though the zoom ring is stiff. Autofocus is fast and quiet. It suits wildlife and sports photographers seeking a compact, long-reach zoom, despite a slow aperture and high price.