Canon EF 16–35mm lens

The EF 16–35 mm lens is a family of professional wide-angle lenses made by Canon Inc. The original version, the EF 16-35mm f/2.8L USM, replaced the EF 17-35mm f/2.8L USM lens, which had itself replaced the EF 20-35mm f/2.8L lens.

The lens has an EF mount to work with the EOS line of cameras. Other than the front element, it is sealed against dust and water, and features a diaphragm which remains nearly circular from f/2.8 to f/5.6.

The EF 16-35mm f/2.8L USM was replaced by the EF 16-35mm f/2.8L II USM early in 2007. The main change saw the lens adopt a new optical design featuring 16 elements in 12 groups. Other changes include a 35 g increase in weight, a larger 82 mm filter diameter and a longer length.

The model II lens has garnered favorable to excellent reviews, and has been used in independent feature films like Marianne which was shot using a Canon EOS 7D.

The next member of the family, the EF 16-35mm f/4L IS USM, was announced in May 2014. While it is one stop slower than the other 16–35 mm versions, it is the first L-series wide-angle zoom to offer image stabilization.

Most recently, Canon announced an upgraded EF 16-35mm f/2.8L III USM in August 2016, with retail availability expected in October of that year. Canon claims that the Mk III version is more durable than the Mk II version, and according to Digital Photography Review, "the Mark III clearly addresses one of its predecessor's largest shortcomings — poor off-center performance".

The EF 16-35mm f/2.8L III USM is Canon's top-end ultra-wide zoom. The f/4 IS USM version is still an L-series lens, but is noticeably less expensive.

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