The EF 16–35mm 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 20–35 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 35g increase in weight, a larger 82mm filter diameter and a longer length.
The new 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 newest 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 16–35mm versions, it is the first L-series wide-angle zoom to offer image stabilization.
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