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Canon EF 70-200mm f/4 USM L IS (full format) - Review / Test Report
introduction
Canon users were always gifted with a broad range of excellent tele lenses, especially zooms. At the time the Canon EF 70-200mm f/4 USM L hit the market back in 1999 it was another milestone but there was one itch left: wouldn't it be nice to have this lens with an image stabilizer ? In late 2006 Canon heard the calls and released the Canon EF 70-200mm f/4 USM L IS so there're now no less than -four- 70-200mm L variants in the lens line-up. However, some user calls probably went silent after seeing the price tag beyond the one grand (€/US$) barrier. Still, for many a wish came true. We have already tested the lens on an APS-C DSLR some time ago (with superb results) but its native playground is the full format so let's have a look how it performs here now.
The build quality of this lens is excellent - no wobbling and smooth controls. The lens does not extend during zooming and thanks to its inner focusing system the front element does not rotate so using a polarizer is no problem - unless you attach the hood of course.
The lens incorporates a new third-generation Image Stabilizer (IS) with a claimed gain of 4 f-stops for hand held photography (at cost of shutter speed). This is achievable in the field but better take 3 f-stops as a guidance. Unlike the consumer variants the IS system has 2 modes - a normal one for static shooting (horizontal + vertical stabilization) and a panning mode (horizontal OR vertical stabilization - the panning direction is automatically detected). It also features tripod detection so the IS can remain activated here.
By default the EF 70-200mm f/4 USM L IS does still NOT come with a dedicated tripod mount but it is available as an option either in black or white. The lens may be relatively light-weight but used on a tripod the camera-lens balance is quite bad so if you intend to use here the optional tripod mount is a good investment.
Typical for most modern EF lenses it features a ring-type USM drive which offers near silent and very fast AF operations. There were no problems with respect to AF accuracy during our field tests either. Like its direct cousins the lens is compatible to the EF 1.4x (-> 98-280mm f/5.6) and EF 2x (-> 140-400mm f/8) converters. Please note that Canon consumer DSLRs will not provide AF with the latter combination due to the small max. aperture.
The similarities between the two 70-200mm f/4 variants are quite striking so let's have a short look at the paperwork here before going on to the test results
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مرجع : http://www.photozone.de/canon_eos_ff...n_70200_4is_5d[/LEFT][/LEFT]