The EF 200-400mm
f/4L IS USM Extender 1.4x, announced yesterday, is the first commercially
available lens to feature a built-in 1.4x extender, allowing the user to extend
its 200-400mm focal length to 280-560mm.

AP’s Technical
Editor Richard Sibley, who has been able to try out the lens, praised the 1.4x
extender for granting photographers much greater adaptability.

If someone were
shooting at the full extent of the focal length, and another subject presented
itself at a much shorter distance, simply deactivating the extender with a
flick of a lever would allow for swift refocusing, he explained.

Sibley went on to
say that, since such a situation would normally require a change of lenses, the
flexibility of the EF 200-400mm f/4L IS USM Extender 1.4x is also an asset in
that it will reduce need for frequent lens changes and thus reduce the chances
of dust entering a camera body.

Canon’s L-series
of EF lenses is generally regarded as the firm’s top-of-the-line range with
regard to toughness and reliability in adverse conditions.

The newest member
of the family has a fixed f/4 aperture (increasing to f/5.6 when the extender
is activated), allowing for the use of high shutter speeds, and features a
newly designed optical Image Stabilizer, which Canon claims will provide users
with a four-stop advantage.

The firm drew
particular attention to IS ‘Mode 3′, which applies stabilisation only at the
time of exposure. Canon claims that this will allow photographers to pan with
fast-paced action without having the IS overcompensate for movement.

‘This feature is
ideal for sports photographers, who typically only have a split-second to
capture a subject in front of them,’ Canon said.

The lens includes
Canon’s ring-type Ultrasonic Motor for fast autofocusing. Users can also
override the autofocus at any given moment in order to adjust focus manually.

There are
provisions for video shooters too, with a Power Focus mode that enables an
accurate pull-focus effect, activated by twisting the focus recall ring and
stopping at a preset distance.

Canon claims that
the lens’s magnesium alloy chassis makes it a comparable weight to other
telephoto lenses of similar focal length, despite the additional presence of
the extender.

As is customary
for telephoto lenses in the L-series, the EF 200-400mm f/4L IS USM features
fluorite elements – in this case, fluorine coatings on the front and rear
elements to ward off dirt.

Canon said: ‘The
combination of outstanding optical performance, versatility, weight and tough construction
will make it an essential part of any professional sports or wildlife
photographer’s kitbag.’

The EF 200-400mm
f/4L IS USM will be available from June and is priced at £11,999.99. For more
information visit www.canon.co.uk.