There are wide lenses and ultra-wide lenses, and then there's the Voigtlander 10mm/1:5.6 Hyper Wide Heliar E ($1,099), which is wider than any other rectilinear lens with full-frame coverage. We're reviewing the version for Sony cameras—there's also one for Leica rangefinders, but it's not quite the same exact lens. You can get pretty similar results with Sony's FE 12-24mm F4 G or Canon's EF 11-24mm f/4L, but both are bulkier and more expensive. The Heliar is of those lenses that you may only use for an occasional shot, but nothing else out there will get you the same look. Design: Almost Purely Mechanical The E in the Hyper Wide Heliar E's name refers to Sony's E-mount, used in both its APS-C and full-frame mirrorless cameras. The version of the lens we reviewed can be used with either, although you won't benefit from its extreme angle of view with the smaller APS-C sensor size. Voigtlander also sells it for Leica M cameras, although that version of the lens doesn't focus quite ...
The Voigtlander 10mm/1:5.6 Hyper Wide Heliar E is the widest rectilinear lens you can get for any full-frame camera, but its edges are soft and show a heavy vignette.
Wide field of view; Little barrel distortion; Sharp center; Relatively light and compact
Edge resolution disappoints; Heavy vignette; Manual focus isn't for everyone; Narrow maximum aperture; No filter thread