Vignetting is a minor but noticeable issue with the Canon EF 200-400mm f/4L IS USM Extender 1.4X, chiefly when shooting wide open. This shot was at 560mm, f5.6, 1/1,000 sec., at ISO 200.
See CNET's review of the Canon EF 200-400mm f/4L IS USM Extender 1.4x lens.
July 8, 2013 4:43 PM PDT
Photo by: Stephen Shankland/CNET
| Caption by: Stephen Shankland
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