Canon lens developmentThe availability of three professional Canon lenses that were announced in February has ?yet to be determined?, according to Canon USA.

In a statement outlining ?updates? on the launch dates, Canon did not indicate when the following lenses will go on sale: the revamped EF 500mm f/4L IS II USM and EF 600mm f/4L IS II USM; and the new EF 200-400mm f/4L IS USM Extender 1.4x.

The lenses were announced at the CP+ imaging show in Yokohama, Japan on 9 February.

Amateur Photographer understands that the floods in Thailand are not the cause of the delays.

The revamped 500mm and 600mm super-telephoto lenses, which were due to arrive in ?mid-2011?, are said to be significantly lighter than the previous versions.

The 500mm will cost £8,999, while the 600mm will carry a £11,299 pricetag, according to Canon UK in a statement released earlier this year.

Canon claims that the 600mm is 27% lighter than its predecessor, while the 500mm weighs 17% less.

Claimed features include an improved Image Stabilizer [IS] system, plus the use of Super Spectra Coatings and a SubWavelength Structure Coating to help reduce flare and ghosting.

Meanwhile, the EF 200-400mm f/4L IS USM Extender 1.4x is designed to deliver an increased focal length of ‘280-560mm’.

The Extender was unveiled as a Canon development, and no launch date had originally been given.

A spokesperson for Canon UK said the firm had nothing further to add.