This is my 3rd 400mm f2.8 L lens.. I have owned all three versions, and this IS version is the best by far.. It really smokes the version 1.. and is about as sharp as the MKII version.. but lighter, and easier to hold, hand held, which is how I generally use this lens.. It works wonderfully with my EF teleconverters..(original versions),...which is a real strong point over the version 1 lens.. I'd say it comes close to the sharpness of my 300mm f2.8 L (non IS) but that is a super sharp lens.. It is noticably sharper than version 1 It is very very fast in the AF department... It focuses so close that I can fill the frame too tightly of someone's face! The IS is absolutely a super wonderful addition to this lens.. I shot a test shot of an object in my living room at 1/45ths of a second, hand held, and it was sharp! There is no way I'd shoot under 1/250ths with my non IS version 400mm f2.8 L lenses..

The only thing I miss is the 3 MF speeds to select from, but the faster AF seems to take care of that problem.. The AF preset ring is tricky to get a hold of,...but that is something to learn by using it more and more.. The newly designed tripod collar takes a little getting used to..but it's not a bad design..

I'm a very happy 400mm f2.8 IS L lens owner! :-)

JP

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