Quote Originally Posted by Cory


I already have the 24-105 L IS USM and could potentially just use the doubler on it and buy the 100-400.
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<p style="CLEAR: both"]Cory, the Extender EF 2x won't work on the EF 24-105mm f/4L
<p style="CLEAR: both"]"Inner focusing system with focusing cam Not compatible with Tele Extenders"
<p style="CLEAR: both"]Click here to see the <span style="font-size: x-small;"][url="http://www.bhphotovideo.com/FrameWork/charts/canon2xExtender.html]Extender EF 2x II Compatibility Chart[/url]
<p style="CLEAR: both"]<span style="font-size: x-small;"]I would buy whichever lens you think you'll get more use out of. I own both the EF70-200mm f/2.8 L IS and the EF100-400mm f/4.5-5.6L IS. I bought the EF100-400mm f/4.5-5.6L IS first and if I had it to do all over again I would do it in the same order. Both lenses are amazing but they do quite different things.