Sigma 90mm F2.8 DG | Contemporary (L-Mount)

Reviewers found it very sharp from f/2.8 at normal distances, sharp enough that Amateur Photographer saw moiré in raw files, with only close-up shots looking soft wide open, improving at f/4 and best by f/7.1. Colour fringing is rarely visible, and the nine rounded blades give smooth, pleasant backgrounds for an f/2.8 lens. AF is quick, accurate and quiet, though it can hesitate in dim light and at the closest focus distance. The all-metal build, the metal hood and cap, and the aperture ring are singled out as unusually good for the price.

The weak points are heavy vignetting at f/2.8 and strong pincushion distortion in uncorrected raw files, both of which the design leaves to software. The aperture ring cannot be de-clicked for video, the lens is not fully sealed, and flare resistance is rated anywhere from very good to slightly susceptible when the sun is in frame.

The few L-Mount owner reports read, from Lumix S1R and Sigma fp L users, describe it as an excellent lens with high sharpness and accurate colour.

The only reservation raised is moderate distortion. There are too few reports to judge long-term reliability or quirks.